Spread spectrum with doppler optimization
AssigneeOn-Ramp Wireless, Inc.
InventorsTheodore J. Myers, Daniel Thomas Werner
Life of this patent
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Abstract
A method of compensating for doppler phase errors includes receiving a signal at a receiver wherein the signal is spread using a pseudo-noise code, dividing the signal into a plurality of smaller coherent units and then compensating for induced doppler phase errors by analyzing the plurality of smaller coherent units. Analysis may include producing a plurality of coherent sums by summing across the smaller coherent units and then summing non-coherently the plurality of coherent sums. Analysis may also include demodulating a symbol from the smaller coherent units. A modulation technique may be selected from a plurality of modulation techniques and then be used to encode and transmit a symbol stream.
Claims12
A method of compensating for induced doppler phase errors while communicating through a multiple access spread spectrum communication interface, the method comprising:
- receiving a first signal at a receiver, wherein the first signal is spread using a predetermined pseudo-noise (PN) code;
- dividing the first signal into a plurality of first smaller coherent units;
- summing across each of the plurality of first smaller coherent units to produce a plurality of first coherent sums;
- summing non-coherently the plurality of first coherent sums to detect a magnitude of the first signal;
- selecting a coherent integration length based on the magnitude of the first signal to configure a demodulation;
- receiving a second signal at the receiver, wherein the second signal is spread using the predetermined pseudo-noise (PN) code;
- dividing the second signal into a plurality of second smaller coherent units;
- and
- demodulating a first symbol from the plurality of first smaller coherent units and the plurality of second smaller coherent units comprises cross multiplying the complex conjugate of a unit of the first smaller coherent units with a unit of the second smaller coherent units.
A device for communicating in a spread spectrum system comprising:
- a receiver in communication with a processor and configured to receive a first signal and a second signal, wherein the first signal is spread using a predetermined pseudo-noise (PN) code and the second signal is spread using the predetermined pseudo-noise (PN) code;
- and
- a processor operatively coupled to the receiver and configured to:
- divide the first signal into a plurality of first smaller coherent units,
- sum across each of the plurality of first smaller coherent units to produce a plurality of first coherent sums;
- sum non-coherently the plurality of first coherent sums to detect a magnitude of the first signal;
- select a coherent integration length based on the magnitude of the first signal to configure a demodulation;
- divide the second signal into a plurality of second smaller coherent units;
- and
- demodulate a first symbol from the plurality of first smaller coherent units and the plurality of second smaller coherent units comprises cross multiplying the complex conjugate of a unit of the first smaller coherent units with a unit of the second smaller coherent units.
A spread spectrum communication system comprising:
- a device having a receiver configured to receive a first signal and a second signal, wherein the first signal is spread using a predetermined pseudo-noise (PN) code and the second signal is spread using the predetermined pseudo-noise (PN) code;
- and a processor operatively coupled to the receiver and configured to:
- divide the first signal into a plurality of first smaller coherent units;
- sum across each of the plurality of first smaller coherent units to produce a plurality of first coherent sums;
- sum non-coherently the plurality of first coherent sums to detect a magnitude of the first signal;
- select a coherent integration length based on the magnitude of the first signal to configure a demodulation;
- divide the second signal into a plurality of second smaller coherent units;
- and
- demodulate a first symbol from the plurality of first smaller coherent units and the plurality of second smaller coherent units comprises cross multiplying the complex conjugate of a unit of the first smaller coherent units with a unit of the second smaller coherent units;
- and
- an access point in communication with the device, wherein the access point comprises a transmitter configured to transmit the first signal.
Dependencies are inferred from the claim text.