摘要 |
A radio signal is processed to generate 1-bit signal values. The 1-bit signal values are bitwise logically combined (e.g., XORed) with a 1-bit quantized carrier demodulation template to produce demodulated 1-bit signal values. The demodulated 1-bit signal values are bitwise logically combined (e.g., XORed) with the positioning system modulation code to produce a plurality of 1-bit correlation values. The 1-bit correlation values are arithmetically combined (e.g., summed) to generate a correlation metric. The positioning system modulation code is detected responsive to the correlation metric. The 1-bit signal values may be are arranged into a signal value word that is bitwise logically combined with a carrier demodulation template word to produce a demodulated signal value word. The demodulated signal value word is bitwise logically combined with the positioning system modulation code word to produce a correlation value word. Bits in the correlation value word are arithmetically combined to generate the correlation metric. Such approaches can take advantage of highly parallel processing structures available in some DSP chips.
|