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A wireless transceiver comprises a digital to analog converter having an input for receiving a digital representation of a direct sequence spread spectrum signal and having an analog output. A filter has an input coupled to the analog output of the digital to analog converter. An adder has a first i

A wireless transceiver comprises a digital to analog converter having an input for receiving a digital representation of a direct sequence spread spectrum signal and having an analog output. A filter has an input coupled to the analog output of the digital to analog converter. An adder has a first input coupled to the filtered output and a second input coupled to a loop control voltage generated by a phase lock loop. A VCO integrated into the phase lock loop has a control input coupled to the summed output. An RF output of the VCO produces a continuous phase frequency shift keyed spread spectrum signal in response to the digital representation of the direct sequence spread spectrums signal. A receiver converts received RF signal to baseband in-phase and quadrature that are in turn converted to digitized signals. A demodulator produces chip data that is despread using a matched filter.

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1. A communication device comprising:a digital to analog converter (DAC) having an input for receiving a digital spread spectrum signal and having an analog output; a filter having an input coupled to the DAC analog output and having an output; and a phase locked loop having a voltage controlled osc

1. A communication device comprising:a digital to analog converter (DAC) having an input for receiving a digital spread spectrum signal and having an analog output; a filter having an input coupled to the DAC analog output and having an output; and a phase locked loop having a voltage controlled oscillator (VCO) generating a radio frequency (RF) output; wherein a modulation control signal at the filter output is summed with a control voltage of the VCO such that the VCO is modulated by the modulation control signal to produce a continuous phase frequency shift key modulated RF output signal at a transmit frequency of the communication device. 2. The communication device of claim 1, further comprising a receiver, and wherein a same frequency band is used for both transmission and reception.3. The communication device of claim 2, wherein a receive input signal is time division duplexed (TDD) with a transmit output signal.4. The communication device of claim 3, further comprising:an output filter; and a switch to couple the output filter to the VCO output during a transmit period and to couple the output filter to the receiver during a receive period. 5. The communication device of claim 3, wherein the RF output of the VCO is coupled to the receiver, and wherein the filtered output is summed with the control voltage only during a transmit period.6. The communication device of claim 2, wherein the frequency band is about 902-928 MHz.7. The communication device of claim 1, wherein the digital spread spectrum signal comprises information bits, wherein each information bit is modulated with a twelve chip spreading sequence.8. The communication device of claim 7, wherein an information bit rate is about 100 kilobits per second.9. A communication device comprising:a digital to analog converter (DAC) having an input for receiving a digital spread spectrum signal and having an analog output; a voltage controlled oscillator (VCO) having a control input and a radio frequency (RF) output; a phase detector coupled to the RF output of the VCO and generating a control output; a loop filter having an input coupled to the phase detector control output and an output; an adder having a first input coupled to the loop filter output, a second input coupled to the DAC analog output, and an output coupled to the VCO control input; wherein the VCO output is continuous phase frequency shift key modulated in response to the summed output. 10. The communication device of claim 9, wherein the digital spread spectrum signal comprises a data signal that is modulated using a spreading sequence having an equal number of ones and zeros.11. The communication device of claim 9, wherein the digital spread spectrum signal has minimal information content near 0 Hz.12. The communication device of claim 9, further comprising an analog filter disposed between the DAC output and the second input to the adder, wherein the analog filter attenuates energy at, and near, 0 Hz.13. The communication device of claim 12, wherein the analog filter is a highpass filter.14. The communication device of claim 12, wherein the analog filter is a bandpass filter.15. The communication device of claim 9, wherein a frequency of the VCO RF output is an output frequency of the communication device.16. A method of generating a wireless communication signal comprising:generating a radio frequency (RF) signal at a transmit frequency using a phase lock loop (PLL); converting a digital spread spectrum waveform to an analog representation; generating a modulation control signal by filtering the analog representation; and summing the modulation control signal with a phase lock loop control signal to continuous phase frequency shift key modulate the RF signal. 17. The method of claim 16, wherein the act of filtering the analog representation comprises highpass filtering the analog representation to attenuate frequencies at, or near, 0 Hz.18. The method of claim 16, wherein the act of filtering the analog representation comprises bandpass filtering the analog representation to attenuate frequencies at, or near, 0 Hz.19. The method of claim 16, wherein the digital spread spectrum waveform has minimal information content frequencies at, or near, 0 Hz.20. A system for receiving a spread spectrum signal, the system comprising:a first analog to digital converter receiving an in-phase baseband component of a received signal and producing in-phase digital data; a second analog to digital converter receiving a quadrature baseband component of the received signal and producing quadrature digital data; a frequency shift keying demodulator receiving the in-phase and quadrature digital data and estimating a phase transition between successive chips to produce demodulated chip data; and a matched filter receiving the demodulated chip data and producing estimated bit data. 21. The system of claim 20, wherein a single matched filter is used for receiving the demodulated chip data and producing the estimated bit data.22. The system of claim 20, wherein the frequency shift keying demodulator estimates the phase transition between successive chip by calculating a phase angle between successive chips.23. A method of demodulating a radio frequency spread spectrum signal, wherein data bits are each modulated with a spreading sequence having a series of chips, the method comprising:generating an in-phase baseband component and a quadrature baseband component of the radio frequency spread spectrum signal; converting the in-phase baseband component and quadrature baseband component to an in-phase digital data stream and a quadrature digital data stream, respectively; estimating a phase transition between successive chips to generate a demodulated chip stream; and despreading the demodulated chip stream to produce estimated information bit data. 24. The method of claim 23, wherein a single matched filter is used in despreading the demodulated chip stream.25. A system for demodulating a radio frequency spread spectrum signal, wherein data bits are each modulated with a spreading sequence having a series of chips, the system comprising:means for generating an in-phase baseband component and a quadrature baseband component of the radio frequency spread spectrum signal; means for converting the in-phase baseband component and quadrature baseband component to an in-phase digital data stream and a quadrature digital data stream, respectively; means for estimating a phase transition between successive chips to generate a demodulated chip stream; and means for despreading the demodulated chip stream to produce estimated information bit data. 26. The system of claim 25, wherein a single matched filter is used in the despreading means.