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An improved spread spectrum communication system includes a transmitter and a receiver utilizing a pilot channel for the transmission of pure rather than modulated PN codes for code acquisition or tracking purposes with a lower bit error rate. The pilot signal is used to obtain initial system synchr

An improved spread spectrum communication system includes a transmitter and a receiver utilizing a pilot channel for the transmission of pure rather than modulated PN codes for code acquisition or tracking purposes with a lower bit error rate. The pilot signal is used to obtain initial system synchronization and phase tracking of the transmitted spread spectrum signal. At the transmitter side,

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1. A spread spectrum communication system, comprising:a pilot channel signal generator for generating a pilot signal exhibiting a predetermined binary value;a pseudo-random noise generator for generating first and second pseudo-random noise codes in response to a pseudo-random noise clock ; f

1. A spread spectrum communication system, comprising:a pilot channel signal generator for generating a pilot signal exhibiting a predetermined binary value;a pseudo-random noise generator for generating first and second pseudo-random noise codes in response to a pseudo-random noise clock ; first Walsh orthogonal code generator means for generating a first Walsh orthogonal code according to a first set of Walsh orthogonal code functions, and generating a second Walsh orthogonal code according to a second set of Walsh orthogonal code functions;modulator means coupled to receive an input information signal and the pilot signal, for modulating the pilot signal according to the first Walsh orthogonal code and modulating the input information signal according to the second Walsh orthogonal code to generate a modulated pilot signal and a modulated information signal, respectively; andspreader means for band spreading the modulated pilot signal and the modulated information signal with each of the first and second pseudo-random noise codes to generate a spread spectrum signal to be transmitted via a communication channel. 2. The spread spectrum communication system of claim 1, wherein said spreader means comprises:a first multiplier for multiplying the modulated pilot signal with the first pseudo-random noise code for an in-phase channel to produce an in-phase band spreaded spread pilot signal;a second multiplier for multiplying the modulated pilot signal with the second pseudo-random noise code for a quadrature-phase channel to produce a quadrature-phase band spreaded spread pilot signal;a third multiplier for multiplying the second pseudo-random noise code with a predetermined value to produce an inverted pseudo-random noise code;a fourth multiplier for multiplying the modulated information signal with the first pseudo-random noise code for an in-phase channel to produce an in-phase band spreaded spread information signal;a fifth multiplier for multiplying the modulated information signal with the inverted pseudo-random noise code for a quadrature-phase channel to produce a quadrature-phase band spreaded spread information signal; and a first set of finite impulse response filters connected to the first, second, fourth, and fifth multipliers, for reducing the peaks of the power spectrum density of the in-phase band spreaded pilot and information signals and the quadrature-phase band spreaded pilot and information signals; adder means for combining the in-phase band spreaded spread pilot and signal with the quadrature-phase band spread information signals signal and the quadrature-phase band spreaded spread pilot and signal with the in-phase information signals signal to produce an in-phase signal and a quadrature-phase signal, respectively, for producing said spread spectrum signal to be transmitted via the communication channel ; and upconverter means for upconverting the in-phase signal and the quadrature-phase signal and producing said spread spectrum signal to be transmitted via the communication channel . 3. The spread spectrum communication system of claim 2, wherein said upconverter means comprises:converter means for generating an in-phase analog signal and a quadrature-phase analog signal by converting the in-phase signal and the quadrature-phase signal into an analog format;filter means for generating an in-phase filtered signal and a quadrature-phase filtered signal by low-pass filtering the in-phase analog signal and the quadrature-phase analog signal;first mixer means for multiplying the in-phase filtered signal with an in-phase component of an intermediate frequency signal and the quadrature-phase filtered signal with a quadrature-phase component of the intermediate frequency signal, respectively, and for generating a combined signal based upon the combination of the multiplied results;second mixer means for generating said spread spectrum signal by multiplying the combined signal with a carrier frequency; andamplifier means for amplifying said spread spectrum signal prior to transmission via said communication channel. 4. The spread spectrum communication system of claim 1, further comprising:means for receiving said spread spectrum signal from said communication channel having a received pseudo-random noise code and a received pilot signal modulated therein, and separating an in-phase signal and an quadrature-phase signal therefrom;a second pseudo-random noise generator for generating the first and second pseudo-noise codes, respectively, in response to the pseudo-random noise clock;despreader means for band despreading the in-phase signal and the quadrature-phase signal with each of the first and second pseudo-random noise codes to generate a despreaded in-phase signal and a despreaded quadrature-phase signal;second Walsh code generator means for generating the first Walsh code according to a first set of Walsh functions, and generating the second Walsh code signal according to a second set of Walsh functions;first demodulator means for demodulating the despreaded in-phase signal and the despreaded quadrature-phase signal according to the first Walsh code into a demodulated in-phase signal and a demodulated quadrature-phase signal;pesudo-random noise code control means for receiving the demodulated in-phase signal and the demodulated quadrature-phase signal, and establishing initial synchronization between the received pseudo-random noise code modulated in the received spread spectrum signal and the first and second pseudo-random noise codes by generating the pseudo-random noise clock to control generation of the first and second pseudo-random noise codes; andsecond demodulator means for demodulating the despreaded in-phase signal and the despreaded quadrature-phase signal according to the first and second Walsh codes to produce a demodulated baseband signal. 5. The spread spectrum communication system of claim 4, wherein said receiving means comprises:bandpass filter means for generating a bandpass filtered signal by bandpass filtering the received spread spectrum signal from said communication channel;first mixer means for generating an intermediate frequency signal by multiplying the bandpass filtered signal with a carrier frequency;second mixer means for generating the in-phase signal and the quadrature-phase signal by multiplying the intermediate frequency signal with an in-phase channel component and a quadrature-phase channel component;low-pass filter means for low-pass filtering the in-phase signal and the quadrature-phase signal; andthe quadrature-phase in a digital format. 6. The spread spectrum communication system of claim 5, wherein said pseudo-random noise code control means comprises:pseudo-random code acquisition means for establishing initial synchronization between the received pseudo-random noise code modulated in the received spread spectrum signal and the first and second pseudo-random noise codes;pseudo-random code detector means for detecting the pseudo-random noise codes of the demodulated in-phase and quadrature-phase signals and generating a sync detection signal;pseudo-random noise clock control means for generating a clock control signal corresponding to the sync detection signal; and pseudo-random noise clock generator means for generating the pseudo-random noise clock for controlling generation of the first and second pseudo-random noise codes. 7. The spread spectrum communication system of claim 6 wherein said second demodulator means comprises:a first multiplier for generating a first multiplied signal by multiplying the despreaded quadrature-phase signal with the first Walsh code;a second multiplier for generating a second multiplied signal by multiplying the despreaded in-phase signal with the first Walsh code;a third multiplier for generating a th ird multiplied signal by multiplying the despreaded quadrature-phase signal with the second Walsh code;a fourth multiplier for generating a fourth multiplied signal by multiplying the despreaded in-phase signal with the second Walsh code;accumulator and dump means connected to the first, second, third, and fourth multipliers, for accumulating the first, second, third, and fourth multiplied signals for a predetermined symbol duration;fifth multiplier for generating a combined in-phase signal by multiplying the first multiplied signal accumulated for said predetermined symbol duration with the fourth multiplied signal accumulated for said predetermined symbol duration;a sixth multiplier for generating a combined quadrature-phase signal by multiplying the second multiplied signal accumulated for said predetermined symbol duration with the third multiplied signal accumulated for said predetermined symbol duration; andmeans for obtaining a difference value between the combined in-phase signal and the combined quadrature-phase signal and generating said demodulated baseband signal corresponding to the phase of the difference value. 8. The spread spectrum communication system of claim 4, wherein said pseudo-random noise code control means comprises:pseudo-random code acquisition means for establishing initial synchronization between the received pseudo-random noise code modulated in the received spread spectrum signal and the first and second pseudo-random noise codes;pseudo-random code detector means for detecting the pseudo-random noise codes of the demodulated in-phase and quadrature-phase signals and generating a sync detection signal;pseudo-random noise clock control means for generating a clock control signal corresponding to the sync detection signal; andpseudo-random noise clock generator means for generating the pseudo-random noise clock for controlling generation of the first and second pseudo-random noise codes. 9. The spread spectrum communication system of claim 4, wherein said second demodulator means comprises:a first multiplier for generating a first multiplied signal by multiplying the despreaded quadrature-phase signal with the first Walsh code;a second multiplier for generating a second multiplied signal by multiplying the despreaded in-phase signal with the first Walsh code;a third multiplier for generating a third multiplied signal by multiplying the despreaded quadrature-phase signal with the second Walsh code;a fourth multiplier for generating a fourth multiplied signal by multiplying the despreaded in-phase signal with the second Walsh code;accumulator and dump means connected to the first, second, third, and fourth multipliers, for accumulating the first, second, third, and fourth multiplied signals for a predetermined symbol duration;a fifth multiplier for generating a combined in-phase signal by multiplying the first multiplied signal accumulated for said predetermined symbol duration with the fourth multiplied signal accumulated for said predetermined symbol duration;a sixth multiplier for generating a combined quadrature-phase signal by multiplying the second multiplied signal accumulated for said predetermined symbol duration with the third multiplied signal accumulated for said predetermined symbol duration; andmeans for obtaining a difference value between the combined in-phase signal and the combined quadrature-phase signal and generating said demodulated baseband signal corresponding to the phase of the difference value. 10. A spread spectrum receiver, comprising:means for receiving a spread spectrum signal via an antenna having a pilot signal and an information signal spread by in-phase and quadrature-phase pseudo-random noise codes, respectively, a received pseudo-random noise code and a received pilot signal modulated therein, and separating an in-phase signal and an quadrature-phase signal therefrom;pseudo-random noise generator means for generating first and second pseudo-ra ndom noise codes, respectively, in response to a pseudo-random noise clock;despreader means for band despreading the in-phase signal and the quadrature-phase signal with each of the first and second pseudo-random noise codes to generate a despreaded in-phase signal and a despreaded quadrature-phase signal;Walsh code generator means for generating a first Walsh orthogonal code according to a first set of Walsh orthogonal code functions, and generating a second Walsh orthogonal code signal according to a second set of Walsh orthogonal code functions;first demodulator means for demodulating the despreaded in-phase signal and the despreaded quadrature-phase signal according to the first Walsh orthogonal code into a demodulated in-phase signal and a demodulated quadrature-phase signal;pseudo-random noise code control means for receiving the demodulated in-phase and quadrature-phase signals, and establishing initial synchronization between the received pseudo-random noise code modulated in the received spread spectrum signal in-phase and quadrature-phase pseudo-random noise codes and the first and second pseudo-random noise codes by generating the pseudo-random noise clock to control generation of the first and second pseudo-random noise codes; andsecond demodulator means for demodulating the despreaded in-phase and quadrature-phase signals according to the first and second Walsh orthogonal codes to produce a demodulated baseband signal. 11. The spread receiver of claim 10, wherein said receiving means comprises:bandpass filter means for generating a bandpass filtered signal by bandpass filtering the received spread spectrum signal via said antenna;first mixer means for generating an intermediate frequency signal by multiplying the bandpass fibered filtered signal with a carrier frequency;second mixer means for generating the in-phase signal and the quadrature-phase signal by multiplying the intermediate frequency signal with an in-phase channel component and a quadrature-phase channel component;low-pass filter means for low-pass filtering the in-phase signal and the quadrature-phase signal; andconverter means for converting the in-phase signal and the quadrature-phase signal in a digital format. 12. The spread spectrum receiver of claim 10, wherein said pseudo-random noise code control means comprises:pseudo-random noise code acquisition means for establishing initial synchronization between the received pseudo-random noise code modulated in the received spread spectrum signal in-phase and quadrature-phase pseudo-random noise codes and the first and second pseudo-random noise codes;pseudo-random noise code detector means for detecting the in-phase and quadrature-phase pseudo-random noise codes of the demodulated in-phase and quadrature-phase signals and generating a sync detection signal;pseudo-random noise clock control means for generating a clock control signal corresponding to the sync detection signal; andpseudo-random noise clock generator means for generating the pseudo-random noise clock for controlling generation of the first and second pseudo-random noise codes. 13. The spread spectrum receiver of claim 10, wherein said second demodulator means comprises:a first multiplier for generating a first multiplied signal by multiplying the despreaded quadrature-phase signal with the first Walsh orthogonal code;a second multiplier for generating a second multiplied signal by multiplying the despreaded in-phase signal with the first Walsh orthogonal code;a third multiplier for generating a third multiplied signal by multiplying the despreaded quadrature-phase signal with the second Walsh orthogonal code;a fourth multiplier for generating a fourth multiplied signal by multiplying the despreaded in-phase signal with the second Walsh orthogonal code;accumulator and dump means connected to the first, second, third, and fourth mul tipliers, for accumulating the first, second, third, and fourth multiplied signals for a predetermined symbol duration;a fifth multiplier for generating a combined in-phase signal by multiplying the first multiplied signal accumulated for said predetermined symbol duration with the fourth multiplied signal accumulated for said predetermined symbol duration;a sixth multiplier for generating a combined quadrature-phase signal by multiplying the second multiplied signal accumulated for said predetermined symbol duration with the third multiplied signal accumulated for said predetermined symbol duration; andmeans for obtaining a difference value between the combined in-phase signal and the combined quadrature-phase signal and generating said demodulated baseband signal corresponding to the phase of the difference value. 14. The spread spectrum receiver of claim 11, wherein said pseudo-random noise code control means comprises:pseudo-random noise code acquisition means for establishing initial synchronization between the received pseudo-random noise code modulated in the received spread spectrum signal in-phase and quadrature-phase pseudo-random noise codes and the first and second pseudo-random noise codes;pseudo-random noise code detector means for detecting the in-phase and quadrature-phase pseudo-random noise codes of the demodulated in-phase and quadrature-phase signals and generating a sync detection signal;pseudo-random noise clock control means for generating a clock control signal corresponding to the snyc detection signal; andpseudo-random noise clock generator means for generating the pseudo-random noise clock for controlling generation of the first and second pseudo-random noise codes. 15. A transmitter of a spread spectrum communication system using a pilot channel, comprising: Walsh orthogonal code generating means for generating first and second Walsh orthogonal codes having respective code systems; Walsh modulating means for multiplying a predetermined pilot signal and information signal to be transmitted respectively by said first and second Walsh orthogonal codes and then generating Walsh- modulated pilot and information signals;PN code generating means for generating predetermined first and second pseudo-random noise (PN) codes;first band spread means for multiplying said Walsh- modulated pilot signal by said first and second PN codes to produce band spreaded spread I channel and Q channel pilot signals;second band spread means for multiplying said Walsh- modulated information signals signal by an inverted second PN code and said first PN code to produce band spreaded spread I channel and Q channel information signals;finite impulse response filtering means for finite impulse response filtering and band spreaded spread I channel and Q channel pilot signals and said band I channel and Q channel information signals;first converting means for combining the filtered band spreaded spread I channel pilot signal and the filtered band spreaded I spread Q channel information signal and then converting into an I channel analog signal;second converting means for combining the filtered band spreaded spread Q channel pilot signal and the filtered band spreaded Q spread I channel information signal and then converting into a Q channel analog signal;a low-pass filter for low-pass filtering said I channel and Q channel analog signals to produce I channel and Q channel low-pass filtered signals;a first mixer for multiplying said I channel low-pass filtered signal by an in-phase component of an intermediate frequency signal and multiplying said Q channel low-pass filtered signal by an a quadrature-phase component of said intermediate frequency signal, and then combining the I channel and Q channel multiplied signals which have been mixed with said intermediate frequency signal;a second mixer for multiplying an ou tput signal of said first mixer by a radio frequency signal;a band-pass filter for band-pass filtering an output signal of said second mixer; andan amplifier for amplifying an output signal of said band-pass filter in accordance with a predetermined amplification ratio to produce a baseband signal. 16. The transmitter of claim 15, wherein said second band spread means comprises:a first multiplier for multiplying said second PN code by “−1” to produce said inverted second PN code;a second multiplier for multiplying said Walsh- modulated information signal by aid inverted second PN code to produce the band spreaded spread Q channel information signal; anda third multiplier for multiplying said Walsh- modulated information signal by said first PN code to produce the band spreaded spread I channel information signal. 17. A receiver of a spread spectrum communication system using a pilot channel, comprising:means for receiving a spread spectrum signal from an antenna;a first filter for generting a band-pass filtered signal by band-pass filtering the received spread spectrum signal;a first mixer for multiplying the band-pass filtered signal by a radio-frequency signal and then converting into an intermediate-frequency signal;a second mixer for multiplying the intermediate-frequency signal by an in-phase component and a quadrature-phase component of an intermediate frequency, and generating I channel and Q channel signals in which a carrier frequency has been removed;a second filter for generating low-pass filtered I channel and Q channel signals by low-pass filtering said I channel and Q channel signals;converting means for converting the low-pass filtered I channel and Q channel signals into digital-converted I channel and Q channel signals;PN code generating means for generating first and second PN codes having respective PN code systems in response to a PN clock;I channel despreader means for multiplying the digital-converted I channel signal by said first and second PN codes, and generating a despreaded I channel signal;Q channel despreader means for multiplying the digital-converted Q channel signal by said first and second PN codes, and generating a despreaded Q channel signal; Walsh orthogonal code generating means for generating first and second Walsh orthogonal codes having respective Walsh code systems; #PN code sync control means for Walsh- demodulating said despreaded I channel and Q channel signals with said first Walsh orthogonal code, establishing sychronization of the Walsh demodulated I channel and Q channel signals, and generating the PN clock corresponding to said synchronization;first Walsh demodulating means for receiving and demodulating said despreaded I channel signal in accordance with said first and second Walsh orthogonal codes to produce Walsh- demodulated first and second I channel signals respectively;second Walsh demodulating means for receiving and demodulating said despreaded Q channel signal in accordance with said first and second Walsh orthogonal codes to produce Walsh- demodulated first and second Q channel signals respectively;combining means for multiplying the Walsh- demodulated first and second I channel signals and multiplying the Walsh- demodulated first and second Q channel signals to produce a combined I channel signal and a combined Q channel signal; anddata deciding means for obtaining a difference value between said combined I channel and Q channel signals to produce a baseband signal corresponding to the phase of said difference value. 18. The receiver of claim 17, wherein said PN code sync control means comprises:third Walsh demodulating means for Walsh-demodulating said despreaded I channel and Q channel signals in accordance with said first Walsh orthogonal code;initial sync and sync detection means for establishing synchronization of the Walsh- demodulated first and se cond I channel and Q channel signals and generating a synchronization detection signal corresponding to said synchronization;PN clock control means for outputting a clock control signal corresponding to said synchronization detection signal; andPN clock generating means for generating the PN clock to control generation of said first and second PN codes under the control of said clock control signal. 19. A spreading circuit, comprising:a first spreader having a first input port, a second input port, and an output port exhibiting a first output signal corresponding to a product of a first input signal and a first spreading code signal applied to said first input port and said second input port, respectively,a second spreader having a third input port coupled to said first input port, a fourth input port, and an output port exhibiting a second output signal corresponding to a product of said first input signal and a second spreading code signal applied to said third input port and said fourth input port, respectively;an inverter having a fifth input port coupled to said fourth input port, and an output port exhibiting a third output signal corresponding to an inversion of said second spreading code signal applied to said fifth input port;a third spreader having a sixth input port coupled to receive said third output signal, a seventh input port, and an output port exhibiting a fourth output signal corresponding to a product of a second input signal and said third output signal applied to said seventh input port and said sixth input port, respectively;a fourth spreader having an eighth input port coupled to said second input port, a ninth input port coupled to said seventh input port, and an output port exhibiting a fifth output signal corresponding to a product of said second input signal and said first spreading code signal applied to said ninth input port and said eighth input port, respectively;a first adder providing a sixth output signal by combining said first output signal and said fourth output signal; anda second adder providing a seventh output signal by combining said second output signal and said fifth output signal. 20. The spreading circuit of claim 19, wherein each of said first, second, third and fourth spreader is a multiplier. 21. The spreading circuit of claim 19, further comprised of:a first multiplier disposed to generate an eighth output signal by multiplying said sixth output signal by an in-phase component of an intermediate signal;a second multiplier disposed to generate a ninth output signal by multiplying said seventh output signal by a quadrature phase component of said intermediate signal; anda third adder combining said eighth output signal and said ninth output signal. 22. The spreading circuit of claim 19, further comprised of:a first multiplier disposed to generate an eighth output signal by multiplying said sixth output signal by an in-phase component of an intermediate signal;a second multiplier disposed to generate a ninth output signal by multiplying said seventh output signal by a quadrature phase component of said intermediate signal;a third adder generating a tenth output signal by combining said eighth output signal and said ninth output signal; anda third multiplier disposed to multiply said tenth output signal by a carrier signal. 23. The spreading circuit of claim 19, further comprised of:a first generator providing said first spreading code signal, coupled to said second input port; anda second generator providing said second spreading code signal, coupled to said fourth input port. 24. The spreading circuit of claim 19, further comprised of:a first generator providing said first spreading code signal, coupled to said second input port;a second generator providing said second spreading code signal, coupled to said fourth input port;a third generator providing a first orthogonal code;a fourth generator providing a second orthogonal code;a first multiplier disposed to apply said first input signal to said first input port by multiplying said first orthogonal code by a first applied signal; anda second multiplier disposed to apply said second input signal to said seventh input port by multiplying said second orthogonal code by a second applied signal. 25. The spreading circuit of claim 21, further comprised of:a first generator providing said first spreading code signal, coupled to said second input port;a second generator providing said second spreading code signal, coupled to said fourth input port;a third generator providing a first orthogonal code;a fourth generator providing a second orthogonal code;a third multiplier disposed to apply said first input signal to said first input port by multiplying said first orthogonal code by a second applied signal; anda fourth multiplier disposed to apply said second input signal to said seventh input port by multiplying said second orthogonal code by a first applied signal. 26. A complex spreading circuit, comprising:a first stage disposed to separately spread a first input signal by an in-phase pseudo-random noise code and a quadrature-phase pseudo-random noise code to provide respectively a first output signal corresponding to a product of said first input signal and said in-phase pseudo-random noise code, and a second output signal corresponding to a product of said first input signal and said quadrature-phase pseudo-random noise code;a second stage disposed to separately spread a second input signal by an inversion of said quadrature-phase pseudo-random noise code and by said in-phase pseudo-random noise code, to provide respectively a third output signal corresponding to a product of said second input signal and said inversion of said quadrature-phase pseudo-random noise code, and a fourth output signal corresponding to a product of said second input signal and said in-phase pseudo-random noise code; anda third stage providing a fifth output signal by combining said first output signal with said third output signal, and providing a sixth output signal by combining said second output signal with said fourth output signal. 27. The complex spreading circuit of claim 26, further comprised of a multiplier having a first input port coupled to receive said quadrature-phase pseudo-random noise code and an output port exhibiting said inversion of said quadrature-phase pseudo-random noise code. 28. The complex spreading circuit of claim 26, further comprised of:a first multiplier disposed to generate a seventh output signal by multiplying said fifth output signal by an in-phase component of an intermediate signal;a second multiplier disposed to generate an eighth output signal by multiplying said sixth output signal by a quadrature phase component of said intermediate signal; andan adder combining said seventh output signal and said eighth output signal. 29. The complex spreading circuit of claim 26, further comprised of:a first multiplier disposed to generate a seventh output signal by multiplying said fifth output signal by an in-phase component of an intermediate signal;a second multiplier disposed to generate an eighth output signal by multiplying said sixth output signal by a quadrature phase component of said intermediate signal;an adder combining said seventh output signal and said eighth output signal; anda third multiplier disposed to multiply an output signal of said adder by a carrier signal. 30. The complex spreading circuit of claim 26, further comprised of:a first generator providing a first orthogonal code;a second generator providing a second orthogonal code;a first multiplier disposed to generate said first input signal by modulating a first received signal with said first orthogonal code; anda second multiplier disposed to generate said second input signal by modulating a second received signal with said second orthogonal code. 31. The complex spreading circuit of claim 30, further compris ed of:a third multiplier disposed to generate a seventh output signal by multiplying said fifth output signal by an in-phase component of an intermediate signal;a fourth multiplier disposed to generate an eighth output signal by multiplying said sixth output signal by a quadrature phase component of said intermediate signal;an adder combining said seventh output signal and said eighth output signal; anda fifth multiplier disposed to multiply an output signal of said adder by a carrier signal. 32. A method of spreading first and second input signals with first and second spreading code signals in a transmitter of a spread spectrum communication system, comprising:spreading said first signal with said first and second spreading code signals to produce first and second spread signals, respectively;spreading said second signal with said first and second spreading code signals to produce a third spread signal and an inversion of a fourth spread signal, respectively;producing a first output spread signal by combining said inversion of said fourth spread signal and said first spread signal; andproducing a second output spread signal by combining said second spread signal and said third spread signal. 33. A method of spreading first and second input signals in a transmitter of a spread spectrum communication system, comprising:spreading said first input signal with in-phase and quadrature-phase spreading code signals to produce first and second spread signals, respectively;spreading said second input signal with said in-phase and quadrature-phase spreading code signals to produce a third spread signal and an inverted fourth spread signal, respectively;producing a first output spread signal by adding said inverted fourth spread signal and said first spread signal; andproducing a second output spread signal by adding said second spread signal and said third spread signal. 34. A spread spectrum signal, comprising:a first signal in-phase spread produced by multiplying said first signal with an in-phase pseudo-random noise code, combined with a second signal quadrature-phase spread produced by multiplying said second signal with an inversion of a quadrature-phase pseudo-random noise code; anda first signal quadrature-phase spread produced by multiplying said first signal with said quadrature-phase pseudo-random noise code, combined with said second signal in-phase spread produced by multiplying said second signal with said in-phase pseudo-random noise code. 35. A method of spreading first and second input signals with first and second spreading code signals in a transmitter of a spread spectrum communication system, comprising:spreading said first signal with said first and second spreading code signals to produce first and second spread signals, respectively;spreading said second signal with said first and second spreading code signals to produce third and fourth spread signals, respectively;producing a first output spread signal by subtracting said fourth spread signal from said first spread signal; andproducing a second output spread signal by adding said second spread signal and said third spread signal. 36. A circuit for spreading first and second input signals with first and second spreading code signals in a tranmitter of a spread spectrum communication system comprising:a first stage disposed to spread said first input signal with said first and second spreading code signals to produce first and second spread signals, respectively;a second stage disposed to spread said second input signal with said first and second spreading code signals to produce a third spread signal and an inversion of a fourth spread signal, respectively;a third stage producing a first output spread signal by combining said inversion of said fourth spread signal and said first spread signal; anda fourth stage producing a second output spread signal by combining said second spread said and said third spread signal. 37. A circuit fo r spreading first and second input signals in a transmitter of a spread spectrum communication system, comprising:a first stage disposed to spread said first input signal with in-phase and quadrature-phase spreading code signals to produce first and second spread signals, respectively;a second stage disposed to spread said second input signal with said in-phase and quadrature-phase spreading code signals to produce a third spread signal and an inverted fourth spread signal, respectively;a third stage producing a first output spread signal by adding said inverted said fourth spread signal and said first spread signal; anda fourth stage producing a second output spread signal by adding said second spread signal and said third spread signal. 38. The method of claim 32, further comprised of generating said inversion of said fourth spread signal by inverting said second spreading code signals prior to said spreading of said second signal with said second spreading code signals. 39. The method of claim 33, further comprised of generating said inverted fourth spread signal by inverting said quadrature-phase spreading code signals prior to said spreading of said second input signal with said quadrature-phase spreading code signals. 40. The circuit of claim 36, wherein said second stage further comprises an inverter coupled to apply an inversion of said second spreading code signals to produce said inversion of said fourth spread signal. 41. The circuit of claim 37, wherein said second stage further comprises an inverter coupled to apply an inversion of said quadrature-phase spreading code signals to produce said inverted fourth spread signals.