Spread spectrum signal processing
View Patent ↗The present invention relates to processing of spread spectrum signals, where a continuous signal of a comparatively high frequency is received. This signal is sampled at a basic sampling rate whereby a resulting sequence of time discrete signal samples is produced, which are in turn quantized into a corresponding level-discrete sample value. A plurality of data words are formed, which each includes one or more consecutive sample values. Information obtained from these data words is correlated with at least one representation of a signal source specific code sequence, which has been pre-generated in the form of a code vector. The correlation step specifically involves correlating at least each vector in a sub-group of the code vectors with at least one vector that has been derived from the data word. Thereby resulting data is produced.
1. A software receiver comprising:
a receiver capable of receiving a radio signal;
means for digitizing the radio signal; and
a software correlator capable of mixing the digitized radio signal to form a baseband signal using bit-wise parallelism.
2. The software receiver of claim 1 wherein said software correlator comprises:
means for computing correlations between the baseband signal and at least one pseudo-random number (PRN) code using the bit-wise parallelism.
3. The software receiver of claim 2 wherein said software correlator further comprises:
means for computing accumulations from the correlations using the bit-wise parallelism.
4. The software receiver of claim 3 further comprising:
application-specific code capable of computing navigation data using the accumulations.
5. The software receiver of claim 1 wherein said means for digitizing comprises:
means for down-converting the radio signal to an intermediate frequency; and
a digitizer capable of digitizing the intermediate frequency.
6. The software receiver of claim 5 wherein said digitizer produces at least one bit/sample.
7. The software receiver of claim 5 wherein said digitizer is an analog to digital converter.