Antenna System

The present invention relates to a radar system and more particularly to an antenna system adapted to be used for a radar system which employs a phased array method for the transmission system and a digital beam forming method for the reception system.

The present invention relates further to a mounting method for integrated circuits containing microwave circuits suitable for the transmission/reception systems of an antenna system.

An example of the constitution of an antenna system of this type according to the prior art is illustrated in FIG. 1. In FIG. 1, numeral 1 designates an element antenna, numeral 2 a miniature transmitter/receiver, numeral 4 an entire reception signal converting unit, numeral 5 a distributor, numeral 6 a transmission signal/reception signal switching unit, numeral 7 a frequency converter, numeral 8 a band-pass filter, numeral 9 an analog/digital converter, numeral 10 an electro/optical converter, numeral 11 a signal processing unit and numeral 12 an input terminal.

FIG. 2 illustrates an example of the interior constitution of the miniature transmitter/receiver 2 shown in FIG. 1. In FIG. 2, numeral 13 designates a phase shifter, numeral 14 a transmission/reception switch, numeral 15 a high power amplifier, numeral 16 a low-noise amplifier and numerals 17 and 18 input and output terminals.

FIG. 3 illustrates an example of the interior constitution of the transmission signal/reception signal switching unit 6 shown in FIG. 1. In FIG. 3, numeral 19 designates a switch, numeral 20 an input/output terminal and numerals 22, 23 output terminals.

Operation of an antenna system according to the prior art will now be explained with reference to FIGS. 1-3.

The signals input to the input terminal 12 as the time sharing signals comprised of the transmission signals and the local oscillation signals from an external apparatus will be input to the transmission signal/reception signal switching unit 6 in each of a plurality of reception signal converting units 4 via the distributor 5. The transmission signal/reception signal switching unit 6 is constituted as shown in FIG. 3, wherein, in a transmission mode, the two switches 19a, 19b are switched in synchronization with the transmission signals to apply only the transmission signals of the input signals to the input/output terminal 21. In the mean time, in a reception mode, the switches 19a, 19b are switched in synchronization with the local oscillation signals, so that the local oscillation signals alone are output to the output terminal 23 while the reception signals from the input/output terminal 21 alone are applied to the output terminal 22 by the switch 19b.

The transmission signals which have been separated by the transmission signal/reception signal switching unit 6 are input to the miniature transmitter/receiver 2, such as the transmitter/receiver 2-1a. The miniature transmitter/receiver 2-1a is constituted as shown in FIG. 2, so that the transmission signals input to the input/output terminal 17 are input to the phase shifter 13 through the transmission/reception switching unit 14a and after controlled in a digital manner so as to attain a predetermined transmission phase, they are amplified by the high power amplifier 15 and then output to the output terminal 18 by way of the transmission/reception switch 14b. The transmission signals are then emitted in the air by way of the element antenna 1-1a connected to the input/output terminal 18. Since the antenna system consists of a plurality of the reception signal converters (4-1a-4-Nm), the miniature transmitters/receivers (2-1a-2-Nm) and the element antennas (1-1a-1-Nm), the phases of the transmission signals (or the transmission electric waves) can be aligned by controlling the phase shifter 13 in corporate in each of the miniature transmitters/receivers (2-1a-2-Nm) and the power of the transmission signals can be concentrated in a desired direction. (As explained above, the radar method which synthesizes the transmission electric waves from the respective element antennas in the air and provides the transmission electric waves with directivity is referred as the phased array radar.)

On the other hand, the reception signals input from the element antenna 1-1a are amplified by the low noise amplifier 16 by way of the transmission/reception switch 14b incorporated in the miniature transmitter/receiver 2 and output to the input/output terminal 17 by way of the transmission/reception switching unit 14a and then input to the reception signal converting unit 4-1a. Operation of the transmission signal/reception signal switching unit 6 incorporated in the reception signal converting unit 4-1a causes the reception signals to be input from the input terminal 12 and synchronized with the local oscillation signals which have been distributed by the distributor, and to be input to the frequency converter 7 respectively. In this frequency converter 7, the reception signals and the local oscillation signals are mixed up and converted to the intermediate frequency reception signals. The reception signals are then sent to the band-pass filter 8 adapted to remove unnecessary frequency signals which have been generated due to the mixing, and are converted into digital signals by the A/D converter 9 and further are converted into optical digital reception signals by the electro/optical converter 10 to be input to the signal processing unit 11. The antenna system is provided with a plurality of the circuit systems having the functions as explained above in a similar manner to the transmission system. The optical digital signals output from the respective reception signal converters (4-1a-4-Nm) are then input to the signal processing unit 11, which in turn synthesizes the input signals from the respective element antennas (1-1a-1-Nm) instantaneously by a high speed operation to provide the signals with a desired directivity. (The radar system in which the reception signals from the respective element antennas are processed at a high speed so that the reception power can be synthesized instantaneously is referred as a digital beam forming radar).

This digital beam forming radar enables the input signals from the respective antenna elements to be weighted. Accordingly if the element antennas are arranged on a given profiled surfaces such as the surface of an aircraft body or the like, the side lobe level generated in the reception antenna pattern characteristics provided by synthesizing the reception signals may be so easily controlled that an ideal antenna pattern may be formed.

It is to be noted in the circuit constitution as described above that the electro/optical converter 10 is essential for transmitting the reception signals to the signal processing unit 11 without distorting them if they are converted to digital signals at a high speed by the A/D converter 9 and a compact construction may thereby be attained.

The antenna system according to a prior art is constituted as explained above. However, it has caused such problems as requiring a large scale circuit, the power consumption of the A/D converter 9 and the electro/optical converter 10 necessary for high speed signal processing is considerable, and so forth, resulting in difficulty in applying it for installation on an aircraft having strict limitation in terms of weight, dimension and power consumption.

FIG. 4(a) is the front view illustrating an example of the integrated circuit incorporating the micro wave circuit to be used for the antenna system, provided according to the mounting method of a prior art. FIG. 4(b) and FIG. 4(c) are respectively the side elevation of FIG. 4(a). It is to be understood that for convenience of illustration of the mounting condition the enclosure cover has been removed. In FIG. 4, numeral 41 designates a micro wave integrated circuit, numeral 42 input/output pads for the high frequency signals provided on the microwave integrated circuit 41, numeral 43 input/output pads for drive signals provided on the micro wave integrated circuit 41, numeral 44 a drive circuit adapted to drive the micro wave integrated circuit 41, numeral 45 input/output pads for drive signals provided on the drive circuit 44, numeral 48 a high frequency connector for inputting high frequency signals from outside and outputting the same to outside, numeral 49 connector pins adapted to input the external control signals to the drive circuit 44, numeral 47 gold wires connecting the connector pins 49 and the input/output pads 45 for drive signals, the input/output pads 43 for drive 43 for drive signals and the input/output pads 43 for drive signals and the input/output pads 42 for high frequency signals and the high frequency connectors 48, and the numeral 40 designates an accommodation casing. For simplicity of description, components attached on the micro wave integrated circuit 41 and the drive circuit 44 are omitted.

Operation of the integrated circuit will next be explained. The high frequency signals input from the high frequency connector 48a are input to the microwave integrated circuit 41 via the metallic wire 47c and the input/output pad 42a for high frequency signals. On the other hand, the drive circuit 44 provides predetermined drive signals corresponding to the external control signals input from the connector pins 49, so that the high frequency signals being transmitted in the micro wave integrated circuit 41 are set at a predetermined level and are output to the external device by way of the input/output pad 42b for the high frequency signals, the gold wire 47f and the connector 48b for high frequency signals.

Since the micro wave integrated circuit 41 and the associated drive circuit 44 have been mounted on plane relative to each other like in the manner of the integrated circuit of a prior art as shown in FIG. 4, the longitudinal dimension of these circuits in the mounted condition had to be long, and since the components to be installed on the micro wave integrated circuit 41 are those for high frequency signal, the height of those components had to be far lower than that of the components installed on the drive circuit 44, this caused loss in the mounting space, leaving the problems to be solved in view of a high density mounting.

FIG. 5(a) is the front view of mounting illustrating the second example of the integrated circuit provided according to a prior art mounting method. FIG. 5(b) is the side elevation of FIG. 5(a). FIG. 6 is the sectional view taken along the line A--A' in FIG. 5(a). It is to be understood that for clear illustration of the mounting condition, the seal cover is removed. In FIG. 5(a), numeral 51 designates a first micro wave integrated circuit, numeral 52 input/output pads provided on the first micro wave integrated circuit 51, numeral 53 are second micro wave integrated circuit, numeral 54 input/output pads provided on the second micro wave integrated circuit 53, numeral 55 a a metallic conductor adapted to install the first micro wave integrated circuit 51 and the second micro wave integrated circuit 53, numeral 59 a metallic frame for sealing, numeral 70 a dielectric member, numeral 60 strip tracks formed on the dielectric member 70, numeral 71 a dielectric member for electrically insulating the metallic frame 59 for sealing and the strip tracks 60 and numeral 61 gold wires connecting the input/output pads 52 for the first micro wave integrated circuit, the input/putput pads 54 for the second microwave integrated circuit and the strip tracks 60. It is to be noted that for the sake of simplying the explanation the components to be installed on the first micro wave integrated circuit 51 and the second micro wave integrated circuit 53 are omitted.

Operation of the above-described circuit will next be explained. In FIG. 5(a), the high frequency signals input from the strip track 60a are input to the first micro wave integrated circuit 51 by way of the gold wire 61a, the input/output pad 52a of the first micro wave integrated circuit and are set at a predetermined level, and then are output to the input/output pad 52b of the first micro wave integrated circuit. The signals are further input to the second micro wave integrated circuit 53 by way of the gold wire 61b, the input-output pad 54a of the second micro wave integrated circuit and are set at another predetermined level, and then are output the outside by way of the input/output pad 54b of the second micro wave integrated circuit, the gold wire 61c and the strip track 60b.

Since the first micro wave integrated circuit 51 and the second micro wave integrated circuit 53 which operates as described above, have been mounted on plane relative to each other according to the prior art mounting, as shown in FIG. 5(a), the longitudinal dimension of these circuits had to be long to expand the mounting area, resulting in difficulty in realizing many functions in a limited mounting area. Furthermore as shown in FIGS. 5(b) and 6, since the dielectric member 70 and the dielectric member 71 are embedded in the metallic frame 59 for sealing to constitute the field through provided with a lightness and the external interface, severe machining precision as well as assembly accuracy are required so result in a high cost.

The present invention has been proposed to solve the problems as explained above. Accordingly an object of the present invention is to provide an antenna system wherein the phase shifter 13 incorporated in the miniature transmitter/receiver 2 is shared in operation by the transmission and reception modes, both the transmission and reception operations are executed as a phased array antenna, the element antennas (1-1a-1-Nm) are grouped in blocks and the reception signals can be processed for a digital beam forming technique for each block.

According to the present invention, the element antennas are grouped in blocks for example in the longitudinal direction, and the reception signal converters are provided for each block, whereby the number of the reception signal converters can be considerably reduced and futhermore an antenna system of a compact design and low power consumption can be provided.

Further according to the present invention, the reception signals are processed respectively by the unidimensional phased array radar and the unidimensional digital beam forming radar, whereby the number of the reception signal converters for effecting the digital beam forming can be considerably reduced without detracting from the required radar performance, and an antenna system can be provided which is compact and light due to reduction of the scale of the circuit and of low power consumption due to reduction of the number of the A/D converters and the electro/optical converters affecting the power consumption.

Another object of the present invention is to provide an antenna system wherein the circuit constitution of the reception signal converting unit 4 can be simplified and the transmission system between the reception signal converter and the signal processing unit or an external apparatus can be improved for enhancing the dynamic range of the reception signals and improving the signal processing speed so that the entire antenna system can be made compact and light as well as to consume less power.

According to the present invention, there can be provided an antenna system wherein the signals output from the reception signal is transmitted in the analog form directly as the intermediate frequency signals, or in the opto-analog form by directly converting the intermediate frequency signals to the optical signals, or the micro wave signals which are the transmission signals or the local oscillation signals from an external apparatus are transmitted by optically modulating the micro wave signals, so that the antenna system can be made compact and light and consume less power.

Still further according to the present invention, there can be provided an antenna system wherein the constitution of the reception signal converter can be simplified, and additionally the A/D converters and the serial/parallel digital conversion sections contained in the electro/optical converters can be dispensed with, so that the antenna system can be compact and light and consume less power. Furthermore, such an antenna system may be provided as an optical system is employed of the transmission system for the transmission signals and the local oscillation signals and thus the antenna system as a whole can be light.

An additional object of the present invention is to improve the mounting density of an integrated circuit including a micro wave circuit, for use in an antenna system as described above.

The present invention further has another object to provide an integrated circuit which has enhanced the mounting density by accommodating a micro wave integrated circuit and the drive circuit associated with such a micro wave integrated circuit in an accomodation casing having a multi-layer ceramic layer structure and reducing the tracks on the same plane by utilizing the through-holes in the multi-layer ceramic for wiring.

Still another object of the present invention is to provide an integrated circuit which has enhanced the mounting density by accommodating a micro wave integrated circuit and the drive circuit associated with such a micro wave integrated circuit in an accommodation casing having a layer structure and disposing them vertically so as to reduce the longitudinal dimension and also reducing the ineffective space over the micro wave integrated circuit.

A further object of the present invention is to provide an integrated circuit which has enhanced the mounting density by providing high frequency connectors adapted to feed high frequency signals to a micro wave integrated circuit and connector pins adapted to supply external control signals and a power signal to a drive circuit for the micro wave integrated circuit at the underside surface of the accommodation casing so as to reduce the longitudinal dimension of the integrated circuit.

According to the present invention, since the micro wave integrated circuit and the drive circuit for the micro wave integrated circuit are accommodated in the accommodation casing having a layer structure made of a multi-layer ceramic and the through holes in the multi-layer ceramic are utilized for wiring, the number of the tracks provided on the same plane can be reduced and the mounting density can be enhanced.

Further according to the present invention, the micro wave integrated circuit and the drive circuit for the micro wave integrated circuit are accommodated in the accommodation casing having a layer structure and they are disposed vertically, so that the longitudinal dimension of the integrated circuit can be reduced and the ineffective space over the micro wave integrated circuit can be reduced and the mounting density can be enhanced.

Also according to the present invention, the high frequency connectors adapted to feed the high frequency signals to the micro wave integrated circuit and the connector pins adapted to supply the external control signals and the power signal to the drive ciruit for the micro wave integrated circuit are provided and connected on the underside surface of the accommodation casing so as to reduced the longitudinal dimension of the integrated circuit.

Another object of the present invention is to provide a package for a micro wave integrated circuit in which the micro wave integrated circuit is mounted in a hierarchical manner so as to reduce the mounting area and the productivity is enhanced by dispensing with strict machining precision, etc. required for the field through portions.

It is also an object of the present invention to provide a micro wave integrated circuit by mounting a plurality of micro wave integrated circuits in an accommodation package in a hierarchical manner, the package having a layer structure provided by a multi-layer dielectric member so as to contract the mounting area.

The present invention still has another object to attain the electrical connection of the micro wave integrated circuit having vertical mounting by forming micro strip tracks, triplate tracks, and coaxial tracks on a multi-layer dielectric member and constituting a means transforming high frequency transmission tracks in a horizontal-vertical-horizontal direction.

Still a further object of the present invention is to provide a micro wave integrated circuit wherein a through hole of a horse shoe type is formed through a dielectric member and metallic material is filled therein so as to provide an external conductor for the coaxial tracks, whereby coaxial tracks can be formed in the dielectric member.

Another object of the present invention is to provide a micro wave integrated circuit wherein the machining accuracy and assembly accuracy can be improved by overlapping the feed through portions and the dielectric member.

Still another object of the present invention is to provide a micro wave integrated circuit wherein through holes are provided at the circumference of the respective layers of a multi-layer dielectric member and these through holes are connected to compose an electromagnetic shield.

According to the mounting method of the micro wave integrated circuit of the present invention, since a plurality of micro wave integrated circuits can be mounted in a hierarchical manner in the accommodation package having a layer structure provided by a multi-layer dielectric member, a micro wave integrated circuit having multi functions in a limited mounting area can be provided.

FIG. 1 is the block diagram illustrating the antenna system according to a prior art;

FIG. 2 is the block diagram illustrating the miniature transmitter/receiver to be used for the antenna system according to a prior art shown in FIG. 1;

FIG. 3 illustrates the constitution of the transmission reception signal switching unit to be provided in the reception signal converting unit shown in FIG. 1;

FIG. 4 illustrates the first example of the integrated circuit including a micro wave circuit in accordance with the mounting method of a prior art, FIG. 4(a) is the front view of the integrated circuit and FIG. 4(b) and FIG. 4(c) are respectively the side elevations thereof;

FIG. 5 illustrates the second example of the integrated circuit in accordance with the mounting method of a prior art, FIG. 5(a) is the front view of the integrated circuit and FIG. 5(b) is the side elevation thereof;

FIG. 6 is the sectional view taken along the line A--A' in FIG. 5(a);

FIG. 7 is the block diagram illustrating a first embodiment of the antenna system according to the present invention;

FIG. 8 is the block diagram illustrating the miniature transmitter/receiver to be used for the antenna system shown in FIG. 7;

FIG. 9 is the block diagram illustrating a second embodiment of the antenna system according to the present invention;

FIG. 10 is the block diagram illustrating a third embodiment of the antenna system according to the present invention;

FIG. 11 is the block diagram illustrating a fourth embodiment of the antenna system according to the present invention;

FIG. 12 is the block diagram illustrating a fifth embodiment of the antenna system according to the present invention;

FIG. 13 illustrates a first embodiment of the integrated circuit in accordance with the mounting method according to the present invention, FIG. 13(a) is the front view of the integrated circuit and FIG. 13(b) and FIG. 13(c) are respectively the side elevations thereof;

FIG. 14 is the sectional view taken along the line B--B' in FIG. 13(a);

FIG. 15 illustrates a second embodiment of the integrated circuit in accordance with the mounting method according to the present invention, FIG. 15(a) is the front view of the integrated circuit and FIG. 15(b) and FIG. 15(c) are respectively the side elevations thereof;

FIG. 16 is the sectional view taken along the line C--C' in FIG. 15(a);

FIG. 17 illustrates a third embodiment of the integrated circuit in accordance with the mounting method according to the present invention, FIG. 17(a) is the front view of the integrated circuit and FIG. 17(b) and FIG. 17(c) are respectively the side elevations thereof;

FIG. 18 is the sectional view taken along the line D--D' in FIG. 17(a);

FIG. 19 is the sectional view taken along the line E--E' in FIG. 17(a);

FIG. 20 illustrates a fourth embodiment of the integrated circuit in accordance with the mounting method according to the present invention, FIG. 20(a) is the front view of the integrated circuit and FIG. 20(b) is the side elevation thereof;

FIG. 21 is the sectional view taken along the line F--F' in FIG. 20(a);

FIG. 22 is the sectional view taken along the line G--G' in FIG. 20(a);

FIG. 23 is the sectional view taken along the line H--H' in FIG. 20(a);

FIG. 24 is the view seen from the arrow I in FIG. 21;

FIG. 25 is the view seen from the arrow J in FIG. 22;

FIG. 26 illustrates the electromagnetic shield in which side through holes are formed inside the integrated circuit;

FIG. 27 illustrates the electromagnetic shield in which the side through holes are formed outside the integrated circuit; and

FIG. 28 illustrates the concrete example of transforming from the micro strip track to the triplate track.

The first embodiment of the present invention will now be explained by referring to FIGS. 7 and 8. In FIG. 7, numeral 70 designates a power supply circuit. The signals input to the input terminal 12 as the time sharing signals composed of the transmission signals and the local oscillation signals from the external apparatus are separated by the reception signal converting unit 4 into the reception signals and the local oscillation signals, similar to the prior art shown in FIG. 1. The transmission signals are output to the power supply circuit 70 and the local oscillation signals are output to the frequency converter 7 respectively.

The transmission signals output from the reception signal converting unit 4, for example, 4-1 are applied to the power supply circuit 70-1. The power supply circuit 70-1 is made up of a plurality of blocks respectively adapted to supply the power signal in the vertical direction (or the lateral direction) depending on the arrangement of the element antenna and to divide the transmission signals. The divided transmission signals are input to a plurality of the miniature transmitters/receivers (2-1a-2-1m) connected to the power supply circuit 70-1. The miniature transmitter/receiver 2 is constituted as shown in FIG. 8. The phases of the transmission signals are controlled by the phase shifter 13 in the same manner as the prior art shown in FIG. 2. After amplified by the high power amplifier 15, the transmission signals are output from the miniature transmitter/receiver 2 and are emitted in the air by way of the element antennas (1-1a-1-1m).

Thus, the phased array radar can be constituted which aligns the phases of the respective transmission signals (transmission electric waves) and concentrates the power in the required direction, the transmission signals being emitted from the element antennas (1-1a-1-Nm) comprising a plurality of the blocked element antennas (1-1a-1-1m).

On the other hand, the reception signals input to the element antennas are applied to the miniature transmitters/receivers (2-1a-2-Nm) connected to the respective element antennas (1-1a-1-Nm), and then are input to the transmission/reception switch 14b shown in FIG. 4. Then the reception signals are synchronized to the reception timing by means of the transmission/reception switch 14b and are input to the low noise amplifer 16, and after amplified by the low noise amplifier, are input to the phase shifter 13 via the transmission/reception switch 14a. After the phase of the reception signals are controlled by the phase shifter 13, they are input to the power supply circuits (70-1-70-N). These power supply circuits (70-1-70-N) are divided into blocks line by line according to the arrangement of the element antennas (1-1a-1-Nm) in the same manner as the transmission system. For example, with regard to the power supply circuit 70-1, the reception signals incident to the element antennas (1-1a-1-Na) are phase shifted in a required direction by the phase shifter 13 incorporated in the miniature transmitters/receivers (2-1a-2-Na) in accordance with the direction of arrangement of the element antennas (1-1a-1-Na), whereby the unidirectional phased array radar for the reception signals can be constituted. The reception signals combined by the power supply circuit (70-1-70-N) are input to the reception signal converting units (4-1-4-N) corresponding to the respective blocks. Then in the same manner as the prior art, frequency conversion, band-pass filtering, A/D conversion and electro/optical conversion are succeedingly executed on the signals, which are input to the signal processing unit 11 as the optical digital signals. In the signal processing unit 11, the reception signals which pass orthogonally the unidirectional phased array radar are subjected to the unidirectional digital beam forming processing between the blocks or between the blocked element antennas (1-1a-1-Na) and the blocked element antennas (1-1m-1-Nm), so that the required reception waves can be obtained.

The second embodiment of the present invention will next be explained with reference to FIG. 9.

The signals input to the input terminal 12 as the time sharing signals comprising the transmission signals and the local oscillation signals from the external apparatus are applied to the respective reception signal converting units 4 by the distributor 5. And in the same manner as the embodiment shown in FIG. 7, the input signals are separated by the reception signal converting units 4 into the transmission signals and the local oscillation signals. The transmission signals are applied to the power supply circuits 70 and the local oscillation signals are applied to the frequency converters 7 respectively.

The transmission signals output from the reception signal converting units 4, for example 4-1, are input to the power supply circuit 70-1. The power supply circuit 70-1 is consisted of a plurality of blocks respectively adapted to supply the power signal in the vertical direction (or in the lateral direction) depending on the arrangement of the element antennas and to divide the transmission signals. The divided transmission signals are input to a plurality of the miniature transmitters/receivers ( 2-1a-2-1m) connected to the power supply circuit 70-1. In the miniature transmitters/receivers 2, the phases of the transmission signals are like in the embodiment shown in FIG. 8 controlled by the phase shifter 13. After amplified by the high power amplifier 15, the transmission signals are output from the miniature transmitters/receivers 2 and emitted in the air by way of the element antennas (1-1a-1-1m).

On the other hand, the reception signals incidental to the element antennas are applied to the transmission/reception switch 14b of the miniature transmitters/receivers (2-1a-2-Nm) connected to the respective element antennas (1-1a-1-Nm). The signals are then synchronized to the reception timing by the transmission/reception switch 14b and are input to the low noise amplifier 16. After amplified by the low noise amplifier, they are input to the phase shifter 13 by way of the transmission/reception switch 14a. The phases of the reception signals are controlled by the phase shifter 13 and are input to the power supply circuits (70-1-70-N). These power supply circuits (70-1-70-N) are divided into blocks line by line according to the arrangement of the element antennas (1-1a-1-Nm) in the same manner as the transmission system. For example with regard to the power supply circuit 70-1, the reception signals incidental to the element antennas (1-1a-1-Na) are phase shifted by the phase shifters 13 incorporated in the miniature transmitters/receivers (2-1a-2-Na) in accordance with the direction of arrangement of the element antennas in a required direction, so that the unidirectional phased array radar for the reception signals can be constituted. The reception signals combined by the power supply circuits (70-1-70-N) are input to the reception signal converting units (4-1-4-N) corresponding to the respective blocks, and the reception signals are input to the frequency converter 7 by the transmission/reception switching unit 6 while the local oscillation signals from the input terminals 12 are input to the frequency converter 7. In the frequency converter 7, the reception signals and the local oscillation signals are mixed together to be converted to intermediate frequency reception signals. The resulting reception signals are passed through the band-pass filter 8 which is adapted to remove unnecessary waves caused by the mixing, and are output to the signal processing unit 11 by way of the coaxial cable, twist pair cable, flexible printed substrate or the like and subjected to the digital beam forming process as explained above.

As explained above, the reception signal converting unit 4 according to the present invention is capable of dispensing with the A/D converter, the electro/optical converter (in particular the parallel/serial digital converting section) which consume much power, thereby attaining a compact and light construction of low power consumption.

FIG. 10 illustrates the third embodiment of the present invention. In FIG. 10, numeral 101 designates a second frequency converter, numeral 102 a second band-pass filter, numeral 103 a second local oscillation signal input terminal and numeral 104 a second distributor.

In FIG. 10, the method of frequency conversion by the reception signal converting unit 4 is changed from the signal conversion method as shown in FIG. 9 to the double conversion method, wherein the intermediate frequency reception signals generated by the frequency converter 7 and the band-pass filter 8 are further mixed at the second frequency converter 101 with the second local oscillation signals input from the second local oscillation signal input terminal 103 and output by the second distributor 104 to the respective reception signal converting units 4 to be converted to the second intermediate frequency reception signals, which are in turn output to the signal processing unit by way of the second band-pass filter 102 adapted to remove the unnecessary waves generated by the second frequency converter 101. This system enables the band-pass range width of the second band-pass filter 102 to be narrower than the band-pass filter 8, so that the ratio of signal to noise power in the passage band-pass width can be improved, and the reception system having higher sensitivity can be constituted.

FIG. 11 illustrates the fourth embodiment of the present invention wherein the numeral 110 designates an electro/optical converter adapted to directly effect the electro/optical conversion of the intermediate frequency reception signals.

Operation of the system shown in FIG. 11 is identical to that of the system shown in FIG. 9 except the reception signal converting units 4. After the unnecessary waves are removed from the intermediate frequency reception signals generated by the frequency converter 7 by the band-pass filter 8, the intermediate frequency reception signals are input to the electro/optical converter 110. The electro/optical converter 110 uses the analog signals which are the intermediate frequency reception signals as the modulation signals in the optical transmission system and transmits the optical signals in the analog form. Therefor, since, in FIG. 7, the analog/digital converter 9 and the parallel/serial digital conversion section incorporated in the electro/optical converter 10 adapted to convert the parallel digital signal output by the converter 9 to optical digital signals can be dispensed with, consumption of power can be largely reduced and the system can be simplified.

FIG. 12 illustrates the fifth embodiment of the present invention and numeral 120 designates an optical/micro wave converter.

Operation of the system shown in FIG. 12 is identical to that of the system shown in FIG. 9 except the system for transmitting the input signals from the external apparatus. The signals input to the input terminal 12 as the time sharing optical analog signals comprised of the transmission signals and the local oscillation signals from the external apparatus are input to the optical/micro wave converter 120. In the optical/micro wave converter 120, the micro wave signals which are the modulated signals for optical transmission are demodulated and the transmission micro wave signals and the local oscillation signals are output in a time-sharing manner and then are applied to the distributor 5 which distributes and outputs the micro wave signals to the respective reception signal converting units 4.

According to the second embodiment through the fifth embodiment of the present invention, the wave guide or the coaxial track which is used between the external apparatus and the input terminal 12 in the first embodiment can be replaced by fine and light optical fibers.

It is to be understood that even if the distributor 5 is replaced by an optical distributor and the optical output signals from the distributor 5 are converted into the micro waves at the input ends of the respective reception signal converting units 4, the function of the present invention may not be impaired.

FIG. 13(a) is the front view showing the first embodiment of mounting of the integrated circuit according to the present invention. FIG. 13(b) and FIG. 13(c) are the side elevations of FIG. 13(a) respectively. FIG. 14 is the sectional view taken along the line B--B' in FIG. 13(a).

In FIG. 14, numeral 140 designates a metallic conductor, numeral 141 a first dielectric member having one side surface joined to the metallic conductor 140 and the other side surface provided with the signal transmission surface, numeral 142 a second dielectric member having one side surface joined to the signal transmission surface of the first dielectric member and the other side surface having the surface for grounding, numeral 143 a third dielectric member having one side surface joined to the grounding surface of the second dielectric member and the other side surface provided with the signal transmission surface, numeral 144 a fourth dielectric member having one side surface joined to the signal transmission surface of the third dielectric member and the other side surface provided with the surface for grounding and numeral 145 a fifth dielectric member having one side surface joined to the grounding surface of the fourth dielectric member and the other side surface provided with the surface for signal transmission. It is to be noted that the dielectric members 141, 142, 143, 144 and 145 are provided therein with through holes 147 for supplying signals and power. Numeral 146 designates a seal ring, and numeral 130 input/output pads for connecting the through holes 147 provided on the fifth dielectric member 145, the micro wave integrated circuit 41 and the drive circuit 44.

Operation of the integrated circuit shown in FIG. 13 and FIG. 14 will next be explained. In FIG. 13, the high frequency signals input to the high frequency connector 48, for example 48a, are applied to the micro wave integrated circuit 41 by way of the gold wire 47e and the input/output pad 42a for the high frequency signals. To the drive circuit 44, there are input the external control signals input by the connector pin 49 by way of the gold wires 47a, 47b, and the input/output pads 45a, 45b. Predetermined drive signals responsive to the control signals are output by way of the gold wires 47c, 47d and the input/output pads 130a, 130b. The output signals are applied to the micro wave integrated circuit 41 by way of the through holes 147a-147d shown in FIG. 14 and the input/output pads 130c, 130d shown in FIG. 13. The high frequency waves being transmitted in the micro wave integrated circuit 41 are set at a predetermined level and transmitted to an external device (not shown) by way of the input/output pads 42b for the high frequency signals, the gold wire 47f and the connector 48b for the high frequency signals.

In this way, wiring on the mounting surface can be reduced by constructing the accommodation casing as a multilayer structure and the mounting density can be enhanced by reducing the longitudinal length of the integrated circuit.

FIG. 15(a) is the front view illustrating the second embodiment of the integrated circuit according to the present invention. FIG. 15(b) and FIG. 15(c) and the side elevations of FIG. 15(a). FIG. 16 is the sectional view taken along the line C--C' in FIG. 15(a).

In FIG. 16, numeral 140 designates a metallic conductor provided on the lower portion of the accommodation casing, numeral 141 a first dielectric member having one side surface joined to the metallic conductor 140 and the other side surface provided with the surface for signal transmission, numeral 142 a second dielectric member having one side surface joined to the signal transmission surface of the first dielectric member 141 and the other side surface provided with the surface for grounding, numeral 143 a third dielectric member having one side surface joined to the grounding surface of the second dielectric member 142 and the other side surface provided with the surface for signal transmission, numeral 144 a fourth dielectric member having one side surface joined to the signal transmission surface of the third dielectric member 143 and the other side surface provided with the surface for grounding and numeral 145 a fifth dielectric member having one side surface joined to the grounding surface of the fourth dielectric member 144 and the other side surface with the signal transmission surface as well as the grounding surface. It is to be noted that the dielectric members 141, 142, 143, 144 and 145 are provided therein with through holes 147 for supplying signals and power.

Numeral 146 designates a seal ring, numeral 148 a signal transmission track provided on the signal transmission surface of the third dielectric member 143, numeral 150 and input/output pad for supplying the drive signals and the power to the micro wave integrated circuit 41 provided on the signal transmission surface of the third dielectric member 143, and numeral 130 input/output pads for the drive signals connecting the drive circuit 44 and the through holes 147.

Operation of the integrated circuit shown in FIGS. 15 and 16 will next be explained. In FIG. 15, the high frequency signals input from the high frequency connector 48a are applied to the micro wave integrated circuit 41 by way of the gold wires 47 and the input/output pads 42 for the high frequency signals. The drive circuit 44 receives the external control signals input from the connector pins 49a, 49b through the gold wires 47 and the input/output pads 45 and outputs predetermined drive signals responsive to the control signals by way of the gold wires 47 and the input/output pads 130. The output signals are input from the input/output pad 43 for the drive signals to the micro wave integrated circuit 41 by way of the through holes 147a-147c, the signal transmission surface of the first dielectric member 141, the through holes 147d, 147e, as shown in FIG. 16, and the input/output pads 150 as shown in FIG. 15, so that the high frequency signals being transmitted in the micro wave integrated circuit 41 are set at a predetermined value and the set signals are transmitted to the external device by way of the input/output pad 42 for the high frequency signals, the gold wires 47 and the connector 48b for the high frequency signals.

In this way, the micro wave integrated circuit and the drive circuit associated with the micro wave integrated circuit are not disposed on a plane but accommodated in the accommodation casing of a multi-layer construction, and the wiring is so connected vertically in the through holes in the multi-layer ceramic member as the accommodation casing that the longitudinal dimension of the casing and the ineffective space over the micro wave integrated circuit are reduced, so that the mounting density can be enhanced.

FIG. 17(a) is the front view illustrating the third embodiment of the integrated circuit according to the present invention. FIG. 17(b) and FIG. 17(c) are the side elevations of FIG. 17(a) respectively. FIG. 18 is the sectional view taken along the line D--D' in FIG. 17(a) and FIG. 19 is the sectional view taken along the line E--E' in FIG. 17(a).

In FIG. 18, numeral 140 designates a metallic conductor provided at the lower portion of the accommodation casing and having a through holes 181 enabling the high frequency connector 48 and the connector pin to extend therethrough, numeral 141 a first dielectric member having one side surface joined to the metallic conductor 140 and the surface for connecting and fixedly mounting the connector pins 49 and the other side surface provided with the surface for signal transmission, numeral 142 a second dielectric member having one side surface joined to the signal transmission surface of the first dielectric member 141 and the other side surface provided with the surface for grounding, numeral 143 a third dielectric member having one side surface joined to the grounding surface of the second dielectric member 142 and the other side surface provided with the surface for signal transmission, numeral 144 a fourth dielectric member having one side surface joined to the surface for signal transmission of the third dielectric member 143 and the other side surface provided with the grounding surface, and numeral 145 a fifth dielectric member having one side surface joined to the grounding surface of the fourth dielectric member 144 and the other side surface provided with the surface for grounding. It is to be noted that the dielectric members 141, 142, 143, 144 and 145 are provided with through holes 147 for supplying signals and power and the dielectric members 141, 142 are provided with through holes 180 for extending the high frequency connector 48 therethrough. Numeral 146 designates a seal ring, numeral 148 a signal transmission track provided on the signal transmission surface of the third dielectric member 143, numeral 150 input/output pads adapted to supplying the drive signals and the power to the micro wave integrated circuit 41 provided on the signal transmission surface of the third electric member 143, and numeral 130 input/output pads for the drive signals for connecting the drive circuit 44 and the through holes 147.

Operation of the integrated circuit shown in FIGS. 17, 18, 19 will next be explained. In FIG. 17, the high frequency signals input from the high frequency connector 48a are applied to the micro wave integrated circuit 41 by way of the gold wire 47c and the input/output pad 42 for the high frequency signals. As shown in FIG. 19, the drive circuit 44 receives the external control signals input from the connector pin 49 by way of the through holes 147e, 147d, 147c, 147b and 147a and the gold wire 47a, and outputs the predetermined drive signals responsive to the control signals to the input pad 43b for the drive signals of the micro wave integrated circuit 41 by way of the gold wire 47d, the through holes 147f, 147g, the signal transmission track 148, the output pad 150c and the gold wire 47c, so that the high frequency signals being transmitted in the micro wave integrated circuit 41 can be set at a predetermined value and be transmitted to the external drive by way of the input/output pad 42 for the high frequency signals, the gold wire 47 and the connector 48b for the high frequency signals.

In this way, the micro wave integrated circuit and the drive circuit associated with the micro wave integrated circuit are not disposed on the same plane but accommodated in the accommodation casing having a layer structure, the wiring is connected vertically in the through holes provided through a multi-layer ceramic member constituting the accommodation casing so that the longitudinal dimension of the integrated circuit can be reduced and the ineffective space over the micro wave integrated circuit is reduced, so that the mounting density can be enhanced. Furthermore, since the high frequency connector for supplying the high frequency signals to the micro wave integrated circuit and the connector pin for inputting the external control signals to the drive circuit in the micro wave integrated circuit are provided on the lower surface of the accommodation casing, the longitudinal dimension of the integrated circuit can be also reduced, so that the mounting density can be enhanced.

FIG. 20(a) is the front view illustrating the fourth embodiment of the integrated circuit according to the present invention. FIG. 20(b) is the side elevation of FIG. 20(a). FIG. 21 is the sectional view taken along the line F--F' in FIG. 20(a). FIG. 22 is the sectional view taken along the line G--G' in FIG. 20(a). FIG. 23 is the sectional view taken along the line H--H' in FIG. 20(a). FIG. 24 is the view as seen from the arrow I in FIG. 21. FIG. 25 is the view as seen from the arrow J in FIG. 22. FIG. 26 illustrates the electromagnetic shield embodied in such a way as to have side through holes inside thereof. FIG. 27 illustrates the electromagnetic shield embodied in such a way as to have side through holes outside thereof. FIG. 28 illustrates a concrete example of transition from the micro strip track using side through holes to the triplate track.

In FIG. 20, numeral 200 designates a first dielectric member having one side surface joined to the metallic conductor 55 and the other side surface provided with the strip track 60, numeral 201 a second dielectric member having one side surface joined to the surface of the first dielectric member 200 forming the strip track and the other side surface provided with grounding patterns, numeral 202 a third dielectric member having one side surface joined to the grounding pattern surface of the second dielectric member 201 and the other side surface provided with the strip track 60, numeral 204 through holes for connecting the second dielectric member 201 and the strip track 60 provided on the third dielectric member 202, numeral 205 grounding patterns formed on the second dielectric member 201, numeral 206 through holes of a horse shoe configuration as an outer conductor which are adapted to form a coaxial track together with the through holes 204 provided in the first dielectric member 200 and the second dielectric member 201, numeral 207 through holes for the electromagnetic shield provided circumferentially in the first dielectric member 200, the second dielectric member 201 and the third dielectric member 202 and connected to the metallic conductor 55 and the metallic frame 203 for seal, numeral 208 through holes provided through the first dielectric member 200 and the second dielectric member 201, and connected to the metallic conductor 55 and the grounding pattern 205, thereby effecting transition between the micro strip track and the triplate track, numeral 209 inside through holes for the electromagnetic shield, which are provided in the first dielectric member 200, the second dielectric numeral 201 and the third dielectric member 202 and are connected to the metallic conductor 55 and the metallic frame 203 for seal, numeral 210 outside through holes for the electromagnetic shield, which are provided at the outside of the first dielectric member 200, the second dielectric member 201 and the third dielectric member 202 and are connected to the metallic conductor 55 and the metallic frame 203 for seal, and numeral 211 side through holes provided through the first dielectric member 200 and the second dielectric member 201 and connected to the metallic conductor 55 and the grounding pattern 205, thereby effecting transition between the micro strip track and the triplate track.

Operation of the integrated circuit shown in FIGS. 20, 21, 22, 23, and 24 will next be explained. The flow of the high frequency signals will first be explained by referring to FIGS. 20(a), 21 and 22. The high frequency signals input from the strip track 60a are applied to the first micro wave integrated circuit 51 through the gold wire 61a and the input/output pad 52a on the first micro wave integrated circuit 51 and are set at a predetermined level. After the set signals are output to the input/output pad 52b on the first micro wave integrated circuit, they are applied to the second micro wave integrated circuit by way of the gold wire 61b, the strip track 60b, the through holes 204a, 204b, the strip track 60c, the gold wire 61c and the input/output pad 54a on the second micro wave integrated circuit and are set at another predetermined level. Then, the set signals are output to the external device by way of the input/output pad 54b on the second micro wave integrated circuit, the gold wire 61d, the strip track 60d, the through holes 204c, 204d and the strip track 60e.

Next, the transition in the horizontal-vertical-horizontal direction of the high frequency transmission path from the first micro wave integrated circuit 51 to the second micro wave integrated circuit will be explained with reference to FIGS. 21 and 24. In FIG. 21, the strip track 60b defines the micro strip track as the high frequency transmission track which is paired with the metallic conductor 55, and is used for connection to the input/output pad 52b on the first micro wave integrated circuit. In order to transform the high frequency transmission track of the micro strip in a vertical direction, the metallic conductor 55 and the grounding pattern 205a are connected by the through holes 208a, 208b for transforming the micro strip track to the triplate track, as shown in FIG. 24, so that they are paired with the strip track 60b to form the triplate track. Also the grounding pattern 205a is paired with the strip track 60c to form the micro strip track for connection to the input/output pad 54a on the second micro wave integrated circuit. Then, the strip tracks 60b and 60c are connected by using the through holes 204a, 204b. Furthermore by means of the through holes 206a and 206b in the form of a horse shoe, the metallic conductor 55 and the grounding pattern 205a are connected to form the coaxial track, so that the propagation direction of the high frequency signals can be changed to the vertical direction.

The transition in the horizontal-vertical-horizontal direction of the high frequency transmission track from the second micro wave integrated circuit 53 to the strip track 60e for outputting externally will next be explained by referring to FIGS. 22 and 25. In FIG. 22, the strip track 60d is paired with the grounding pattern 205c to form the micro strip track and is used for connection to the input/output pad 54b of the second micro wave integrated circuit. Next, the strip tracks 60d and 60e are connected by using the through holes 204c, 204d and further the grounding pattern 205c and the metallic conductor 55 are connected by means of the through holes 206c, 206d in the form of a horse shoe to form the coaxial track for the external conductor of the vertical transition portion. Then, the strip track 60e is paired with the grounding pattern 205c and the metallic conductor 55 to form the triplate track so as to propagate the signals in the horizontal direction. Furthermore, by connecting the metallic conductor 55 and the grounding pattern 205c by means of the through holes 208c, 208d for transforming the micro strip track to the triplate track, the strip track 60e is paired with the metallic conductor 55 to form the micro strip track which is used as the interface for the external device. Although the through holes 208 have been used for transforming the micro strip track to the triplate track, the side through holes 211 may be provided at the end surface of the substrates as shown in FIG. 28, so that the metallic conductor 55 may be connected to the grounding pattern 205a. In case that the through holes cannot be filled with metallic materials having a low resistance, the through holes may be formed as side through holes which are then processed by plating or the like to improve the electrical characteristics.

The electromagnetic shield will next be explained by referring to FIG. 23. As shown in FIG. 23, the througn holes 207 for the electromagnetic shield are provided through the first dielectric member 200, the second dielectric member 201 and the third dielectric member 202 to connect the metallic conductor 55 and the metallic frame 203 for sealing. The electromagnetic shield may be attained by the distance between the through holes for the electromagnetic shield being sufficiently narrow and by sealing the metallic frame 203 by means of the metallic cover.

It is also to be noted that as shown in FIGS. 26 and 27, the outside or inside through holes 209, 210 may be provided on or in the integrated circuit to provide the electromagnetic shield, or if an electromagnetic shield having a fairly high frequency is required, the side through holes may be more effective because of its capability of providing an entire shield or nearly entire shield.