Apparatus and Method for Controlling Power in Code Division Multiple Access System

1. An apparatus for controlling power in a CDMA system, comprising: K number of transmitting antennas; a CDMA base band/IF transmitter processing an input information signal and outputting M number of IF signals in response to K number of independent data channel gains; K number of RF modules converting the M number of IF signals into K number of RF signals and transmitting the converted K number of RF signals through K number of transmitting antennas; a receiver receiving and processing at least one Mobile Station (MS) signal from at least one corresponding mobile terminal, said receiver outputting K number of power control bits and outputting decoded data; and a processor generating and outputting the K number of independent data channel gains to the CDMA base band/IF transmitter in response to said K power control bits to independently control a power level of each of the K number of RF signals.

2. An apparatus of claim 1, wherein the CDMA base band/IF transmitter controls transmission powers of the K number of transmitting antennas in response to the K number of data channel gains.

3. An apparatus of claim 1, wherein the CDMA base band/If transmitter combines the M number of IF signals into K number of IF signals if K<M, said CDMA base band/IF transmitter combining at least two IF signals apart from each other to combine the M number of IF signals into the K number of IF signals.

4. An apparatus of claim 1, wherein said CDMA base band/IF transmitter comprises: an encoder encoding the input information signal and outputting serial data; a DEMUX demultiplexing the serial data and outputting a plurality of subcarrier branch signals; a plurality of IQ mapping units, each performing an IQ mapping operation with respect to a corresponding one of the plurality of subcarrier branch signals and converting the plurality of subcarrier branch signals into a plurality of I and Q channel signal symbols; a plurality of first multipliers, each multiplying a corresponding one of either the I or Q channel signal symbols by a walsh code; a plurality of data channel gain units, each multiplying I and Q channel signal symbols from a corresponding pair of the first multipliers by one of the K number of data channel gains; a plurality of pseudo noise spreading units, each spreading a pair of I and Q channel signals from a corresponding one of the data channel gain units utilizing a pseudo noise code sequence; a plurality of base band filters, each filtering a corresponding one of I and Q channel signal symbols from the pseudo noise spreading units at a predetermined band width; a plurality of second multipliers, each multiplying an I or Q channel signal from a corresponding one of the base band filters by a corresponding one of a plurality of transmission carriers; a plurality of mixers, each mixing I and Q channel signals from a corresponding pair of the second multipliers; and a combiner combining a plurality of carriers from the mixers and outputting M number of IF signals.

5. An apparatus of claim 1, wherein said CDMA base band/IF transmitter comprises: an encoder encoding the input information signal; a data splitter splitting an encoded signal from the encoder; a plurality of IQ mapping units, each performing an IQ mapping operation with respect to a corresponding one of a plurality of split signals from the data splitter and converting the plurality of split signals into I and Q channel signal symbols; a plurality of first multipliers, each multiplying a corresponding one of I and Q channel signal symbols from the IQ mapping units by one of either a first or second walsh code; a plurality of data channel gain units, each multiplying I and Q channel signal symbols from a corresponding pair of the first multipliers by one of the K number of data channel gains; a plurality of pseudo noise spreading units, each spreading I and Q channel signals from a corresponding one of the data channel gain controllers utilizing a pseudo noise code sequence; a plurality of base band filters, each filtering a corresponding one of I and Q channel signals from the pseudo noise spreading units at a predetermined band width; a plurality of second multipliers, each multiplying an I or Q channel signal from a corresponding one of the base band filters by one of either a first or second transmission carrier; and a plurality of mixers, each mixing I and Q channel signals from a corresponding pair of the second multipliers and outputting M number of IF signals.

6. An apparatus for controlling power in a CDMA system, comprising: at least one transmitting antenna; a RF module processing and outputting an input RF signal; a CDMA base band/IF receiver processing and converting the IF signal from the RF module into a baseband signal, said CDMA base band/IF receiver outputting a frame quality indicator and K number of independent estimated power values; a power control unit generating K independent power up/down commands in response to the frame quality indicator and the K number of independent estimated power values; and a transmitter transmitting the K independent power up/down commands from the power control unit at a subcarrier through said at least one transmitting antenna.

7. An apparatus of claim 6, wherein the power control unit comprises: an outer loop power control processor generating a threshold value in response to the frame quality indicator; a comparator comparing the K number of estimated power values with the threshold value from the outer loop power control processor; and a power up/down command generator generating K power up/down commands in response to K compared results from the comparator.

8. An apparatus of claim 6, wherein the CDMA base band/IF receiver includes: a plurality of multipliers, each multiplying the received signal from the RF module by an individual subcarrier; a plurality of low pass filters, each low pass filtering an output signal from a corresponding one of the multipliers; a searcher detecting a timing information from the received signal from the RF module; a pseudo noise generator generating a pseudo noise code sequences in response to the timing information detected by the searcher; a plurality of fingers, each processing the pseudo noise code sequences from the pseudo noise generator and the filtered signal from a corresponding one of the low pass filters, each outputting a first estimated attenuation/phase shift information and I and Q channel signals; a plurality of delay finger sets, each one of the delay finger in the delay finger sets performing the same operation as that of a corresponding one of said plurality of fingers with respect to a delayed filtered signal from a corresponding one of the low pass filters, and outputting a second estimated attenuation/phase shift information and delayed I and Q channel signals; a plurality of combiners, each combining the I and Q channel signals from a corresponding one of the fingers and the delayed I and Q channel signals from a corresponding one of the delay finger sets; a power estimator estimating power in response to the first and second estimated attenuation/phase shift information from the fingers and the delay fingers and in response to the output signals from the combiners, said power estimator outputting the K estimated power values; a multiplexer multiplexing I and Q channel signal symbols from the combiners; and a decoder decoding an output signal symbol from the multiplexer and outputting decoded data, said decoder checking for an error and outputting the frame quality indicator.

9. An apparatus of claim 8, wherein each of the plurality of fingers comprises: a first multiplier multiplying a corresponding one of the output signal samples from the low pass filters and a delayed pseudo noise code sequences from the pseudo noise generator; a second multiplier multiplying an output signal sample from the first multiplier by a walsh code; a first walsh code correlator performing an addition operation with respect to an output signal sample from the second multiplier; a first channel estimator estimating information regarding an attenuation and phase shift resulting from a channel environment utilizing the output signal sample from the first multiplier; a third multiplier multiplying an output signal symbol from the first walsh code correlator by a complex-conjugated signal of an output signal from the first channel estimator; and a first I/Q multiplexer multiplexing an output signal from the third multiplier, and outputting I and Q channel signals.

10. An apparatus of claim 6, wherein said CDMA base band/IF receiver includes: a low pass filter filtering the RF signal at a predetermined band width; a plurality of rake fingers, each processing the output signal sample from the low pass filter, and outputting a first estimated attenuation/phase shift information and I and Q signals; a plurality of sets of delay rake fingers, each delay rake finger of the delay rake finger sets performing the same operation as that of a corresponding one of said rake fingers with respect to a delayed output signal sample from the low pass filter, each outputting a second estimated attenuation/phase shift information and delayed I and Q signals; a plurality of combiners, each adding an output signal from a corresponding one of the rake fingers and output signals from a corresponding one of the delay rake finger sets; a multiplexer multiplexing output signals from said combiners; a power estimator estimating power in response to the estimated attenuation/phase shift information from the rake fingers and the delay rake fingers and in response to the output signals from the adders, said power estimator outputting the K number of estimated power values; and a decoder decoding an output signal from the multiplexer and outputting decoded data, said decoder checking for an error and outputting the frame quality indicator.

11. An apparatus of claim 10, wherein each of the rake fingers comprises: a short PN code generator generating a short PN code sequence in response to a delay control signal from the tracking loop; a first multiplier multiplying the output signal from the low pass filter by a complex-conjugated signal of the short PN code; a second multiplier multiplying an output signal from the first multiplier by the walsh code; a walsh code correlator performing an addition operation with respect to an output signal from the second multiplier; a channel estimator estimating information regarding an attenuation and phase shift resulting from a channel environment utilizing the output signal from the first multiplier; a third multiplier multiplying an output signal symbol from the walsh code correlator by a complex-conjugated signal output from the channel estimator; and a second multiplexer multiplexing an output signal symbol from the third multiplier.

12. A method for controlling power in a CDMA system, comprising the steps of: processing an input information signal and outputting M number of IF signals in response to K number of independent data channel gains; converting the M number of IF signals into K number of RF signals and transmitting the converted K number of RF signals through K number of transmitting antennas; receiving and processing at least one Mobile Station (MS) signal from at least one mobile terminal; outputting K number of power control bits and outputting decoded data; generating and outputting the K number of independent data channel gains in response to said K power control bits; and independently controlling a power level of each of the K number of RF signals using the independent data channel gains.

13. A method of claim 12, wherein in the step of outputting M number of IF signals, controlling transmission powers of the K number of transmitting antennas in response to the K number of data channel gains.

14. A method of claim 12, wherein in the step of outputting M number of IF signals, combining the M number of IF signals into K number of IF signals if K<M.

15. A method of claim 14, wherein in the step of combining the M number of IF signals, combining at least two IF signals apart from each other.

16. A method of claim 12, wherein the step of outputting M number of IF signals comprises the steps of: encoding the input information signal and outputting serial data; demultiplexing the serial data and outputting a plurality of subcarrier branch signals; performing an IQ mapping operation with respect to a corresponding one of the plurality of subcarrier branch signals and converting the plurality of subcarrier branch signals into a plurality of I and Q channel signals; multiplying a corresponding one of either the I or Q channel signals by a walsh code; multiplying the walsh code multiplied I and Q channel signals by one of the K number of data channel gains; spreading the gain control multiplied pair of I and Q channel signals utilizing a pseudo noise code sequence; filtering a corresponding one of pseudo noise spread I and Q channel signals at a predetermined band width; multiplying the filtered I or Q channel signal by a corresponding one of a plurality of transmission carriers; mixing carrier multiplied I and Q channel signals and outputting carrier signals; and combining a plurality of carrier signals and outputting M number of IF signals.

17. A method of claim 12, wherein the step of outputting M number of IF signals comprises the steps of: encoding the input information signal; splitting an encoded signal; performing an IQ mapping operation with respect to a corresponding one of a plurality of split signals from the data splitter and converting the plurality of split signals into I and Q channel signals; multiplying a corresponding one of I and Q channel signals by one of either a first or second walsh code; multiplying the walsh code multiplied I and Q channel signals by one of the K number of data channel gains; spreading the gain multiplied I and Q channel signals utilizing a pseudo noise code sequence; filtering a corresponding one of pseudo noise spread I and Q channel signals at a predetermined band width; multiplying the filtered I or Q channel signal by one of either a first or second transmission carrier; and mixing the carrier multiplied I and Q channel signals and outputting M number of IF signals.

18. A method for controlling power in a CDMA system, comprising the steps of: processing and converting an IF signal into a baseband signal, and outputting a frame quality indicator and K number of independent estimated power values; generating K independent power up/down commands in response to the frame quality indicator and the K number of independent estimated power values; and transmitting the K independent power up/down commands at a subcarrier through a transmitting antenna.

19. A method of claim 18, wherein the step of generating K power up/down commands further comprises the steps of: generating a threshold value in response to the frame quality indicator; comparing the K number of estimated power values with the threshold value; and generating K power up/down commands in response to K compared results.

20. A method of claim 18, wherein the step of processing and converting the RF signal comprises the steps of: multiplying the IF signal by a plurality of individual subcarrier and outputting a plurality of subcarrier signals; low pass filtering each of the plurality of subcarrier signals and outputting a plurality of filtered signals; detecting a timing information from the RF signal; generating a pseudo noise code sequence in response to the timing information; processing the pseudo noise code sequence with each of the plurality of filtered signals, and outputting a plurality of first estimated attenuation/phase shift information and a plurality of PN processed I and Q channel signals; delaying the plurality of filtered signals and outputting a set of delayed signals for each of the plurality of filtered signals; processing the pseudo noise code sequence with each filtered signals of each set of delayed signal, and outputting a plurality of second estimated attenuation/phase shift information and a plurality of delayed I and Q channel signal sets; combining each pair of the plurality of PN processed I and Q channel signals and one of the corresponding delayed I and Q channel signal sets from the plurality of delayed I and Q channel signal sets, and outputting a plurality of added I and Q channel signals; estimating power in response to the first and second estimated attenuation/phase shift information and in response to the plurality of combined I and Q channel signals, and outputting the K estimated power values; multiplexing the plurality of combined I and Q channel signals; and decoding the multiplexed I and Q channel signals and outputting decoded data, and checking for an error and outputting the frame quality indicator.

21. A method of claim 18, wherein the step of processing and converting the RF signal comprises the steps of: low pass filtering the RF signal at a predetermined band width; processing the low pass filtered signal, and outputting plurality of first estimated attenuation/phase shift information and a plurality of I and Q signals; delaying the low pass filtered signal and outputting a set of delayed low pass filtered signals; processing each of the low pass filtered signals of each set, and outputting a plurality of second estimated attenuation/phase shift information and a plurality of delayed I and Q signals sets; combining the plurality of I and Q signals and a corresponding delayed I and Q set from the plurality of delayed I and Q sets, and outputting a plurality of added signals; multiplexing the plurality of combined signals and outputting a multiplexed signal; estimating power in response to the first and second estimated attenuation/phase shift information and the combined signals, and outputting the K number of estimated power values; and decoding the multiplexed signal and outputting decoded data, and checking for an error and outputting the frame quality indicator.

22. An apparatus for controlling power in a CDMA system using diversity antenna, comprising: a CDMA base band/intermediate frequency (IF) transmitter processing an information bit to output M number of IF signals; K number of radio frequency (RF) modules converting the M IF signals from the CDMA base band/IF transmitter into K number of RF signals and transmitting the converted RF signals through K number of corresponding diversity antennae; a receiver receiving a signal from a mobile station through a receiving antenna and processing the received signal to output K number of power control bits and decoded data; a processor generating K number of data channel gains in response to the K number of power control bits from the receiver and outputting the generated K number of data channel gains to the CDMA base band/intermediate frequency transmitter to control transmission powers of the K diversity antennae of base station; a receiving RF module receiving the K number of RF signals from the K diversity antennae of the base station and processing the K received RF signals to output K number of IF signals; a CDMA base band/IF receiver converting the K received RF signals into base band signals and outputting a frame quality indicator and K number of estimated power values; an outer loop power control processor generating a threshold value in response to the frame indicator; a power up/down command generator generating the K number of power control bits in response to K number of compared result from the comparator; and a transmitter to transmit the K number of power control bits.

23. A method for controlling power in a CDMA system, comprising the steps of: receiving and processing an input signal from a mobile terminal; determining K number of power control bits and decoded data from the input signal; generating and outputting K number of data channel gains in response to the K power control bits; processing an information signal and outputting M number of IF signals in response to the K number of data channel gains; converting the M number of IF signals into K number of RF signals with individual power levels and transmitting the converted K number of RF signals through K number of transmitting antennae of base station; receiving and processing the converted K RF signals from K number of transmitting diversity antenna to output K number of IF signals; converting the K IF signals into base band signals and outputting a frame quality indicator and K number of estimated power values; generating a threshold value in response to a frame quality indicator; comparing the K number of estimated power values with the threshold value respectively; generating K number of power control bits in response to K number of compared results; and transmitting the input signal with the K number of power control bits through a transmitting antenna.