liu6747
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Portland, OR
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Hi, All
I am reading Thomas Lee's RF book. On section 19.6.1 (2nd ed, page718), he talked about GPS receiver architecture, which is RF to Low IF (IQ). The themal noise is about ~ 20 dBc higher than GPS signal at RF input, but GPS siganl has 43 dB process gain. The last stage is two 1-bit quantizers, and note 18 says:
Use fo a 1-bit quantizar costs 3 dB, relative to an infinitely fine quantizar. The most commonly used 2-bit quantizar, combined with appropriate AGC to maximize use of the available quantization levels, reduce the loss to about 0.7dB....
I assume the loss is about SNR, but should it be 6dB? because SNR_ADC=1.76+6N?
Please let me know where I am wrong and let me know how to calculate 3 dB on 1-bit adc
thanks
liu
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