Chip blanking and processing in SCDMA to mitigate impulse and burst noise and/or distortion
View Patent ↗Systems and methods are disclosed for detecting temporary high level impairments, such as noise or interference, for example, in a communications channel, and subsequently, mitigating the deleterious effects of the dynamic impairments. In one embodiment, a preliminary decision is made on at least one signal transmitted over the communications channel. The at least one signal is remodulated and the impairment is determined using the at least one remodulated signal.
1. A method of impairment mitigation in a communications system comprising:
making a preliminary decision on at least one signal, wherein making said preliminary decision further comprises blanking at least one symbol;
remodulating said at least one signal;
wiping off said blanked at least one symbol and recreating said at least one symbol; and
determining distortion of at least one signal using said at least one remodulated signal.
2. The method of claim 1 wherein said at least one signal is any orthogonal signal.
3. The method of claim 1 wherein said signal comprises one of at least one digital sample, at least one waveform, at least one chip or at least one symbol.
4. The method of claim 1 , wherein remodulating said at least one signal further comprises taking slicer outputs.
5. A method of mitigating impairment in communications signals, the method comprising:
making a preliminary decision on each of said signals transmitted in at least one spreading frame;
remodulating each of said signals using at least one spreading code;
determining distortion between said remodulated signals and said signals;
identifying at least one suspect signal using said distortion;
blanking said at least one suspect signal;
forming partially remodulated energy for said at least one blanked signal;
reconstructing a composite transmitted value for said at least one blanked signal; and
forming a partial correlation result.
6. The method of claim 5 ,remodulating each of said signals comprises passing said signals through a mass filter and taking slicer outputs.
7. The method of claim 5 , wherein blanking said identified suspect signals further comprises setting a value of said identified signals to zero.
8. The method of claim 5 , further comprising making a hard decision on each of said signals using at least one slicer input.
9. The method of claim 5 , further comprising reconstructing composite transmitted values for each of said blanked signals.
10. The method of claim 5 , further comprising using a partial remodulator to form partially remodulated energy using at least one hard decision.
11. The method of claim 10 , further comprising correlating said partial remodulated energy with said blanked signals.