Multi-carrier receiver with dynamic power adjustment and method for dynamically adjusting the power consumption of a multi-carrier receiver

Abstract

A method for dynamically adjusting the power consumption of a multi-carrier receiver and a multi-carrier receiver with dynamically power adjustment. The method includes receiving a multi-carrier signal, wherein the multi-carrier signal comprises a plurality of sub-carriers. Channel characteristics of each sub-carrier are estimated according to the demodulated multi-carrier signal. ICI strength is estimated from the demodulated multi-carrier signal. A system performance is detected. The estimated ICI is subtracted when the ICI strength exceeds an ICI threshold and the system performance is less than a system performance threshold. The demodulated multi-carrier signal is then equalized is based on the estimated channel characteristics, and the system performance is updated according to the equalized multi-carrier signal.

1 . A multi-carrier receiver with dynamic power adjustment, comprising:
 a demodulator receiving a multi-carrier signal, wherein the multi-carrier signal comprises a plurality of sub-carriers;   a channel estimator estimating channel characteristics of each sub-carrier from the demodulated multi-carrier signal;   an ICI detector estimating an ICI strength of ICI from the demodulated multi-carrier signal;   a system performance detector detecting a system performance;   an ICI canceller subtracting the estimated ICI included in the received multi-carrier signal from the demodulated multi-carrier signal;   a determination circuit turning on the ICI canceller when the ICI strength exceeds an ICI threshold and the system performance is less than a system performance threshold; and   an equalizer equalizing the demodulated multi-carrier signal based on the estimated channel characteristics.   
     
     
         2 . The multi-carrier receiver as claimed in  claim 1 , wherein the determination circuit turns off the ICI canceller when the ICI strength is less than the ICI threshold or the system performance exceeds the system performance threshold. 
     
     
         3 . The multi-carrier receiver as claimed in  claim 1  further comprising a MPE-FEC module, wherein the equalized multi-carrier signal comprises 256 bursts, each burst is marked as either “reliable” or “unreliable”, if all the 256 burst are marked “reliable”, the MPE-FEC module remains off to save power, otherwise, the MPE-FEC module is turned on. 
     
     
         4 . The multi-carrier receiver as claimed in  claim 1 , wherein the demodulator is implemented by an FFT. 
     
     
         5 . The multi-carrier receiver as claimed in  claim 1 , wherein the system performance estimator is signal-to-noise ratio (SNR) estimator, and the system performance is an SNR. 
     
     
         6 . The multi-carrier receiver as claimed in  claim 1 , wherein the system performance estimator is bit error rate (BER) estimator, and the system performance is a BER. 
     
     
         7 . The multi-carrier receiver as claimed in  claim 1 , wherein the ICI detector is a velocity estimator, and the ICI strength the velocity of the OFDM receiver. 
     
     
         8 . The multi-carrier receiver as claimed in  claim 1 , wherein the ICI detector is a Doppler frequency estimator, and the ICI strength is in terms of Doppler frequency. 
     
     
         9 . The multi-carrier receiver as claimed in  claim 1 , wherein the ICI detector is a channel variation estimator, and the ICI strength is in terms of channel variation. 
     
     
         10 . The multi-carrier receiver as claimed in  claim 1 , wherein the multi-carrier signal is an OFDM signal. 
     
     
         11 . The multi-carrier receiver as claimed in  claim 1 , wherein the multi-carrier signal is an MC-CDMA signal. 
     
     
         12 . A multi-carrier receiver with dynamic power adjustment, comprising:
 a demodulator receiving a multi-carrier signal, wherein the multi-carrier signal comprises a plurality of sub-carriers;   a channel estimator estimating channel characteristics of each sub-carrier from the demodulated multi-carrier signal;   an ICI detector estimating an ICI strength of ICI from the demodulated multi-carrier signal;   a system performance detector detecting a system performance;   an ICI canceller subtracting the estimated ICI included in the received multi-carrier signal from the demodulated multi-carrier signal;   a determination circuit turning on the ICI canceller when the system performance is less than a system performance threshold; and   an equalizer equalizing the demodulated multi-carrier signal based on the estimated channel characteristics.   
     
     
         13 . A multi-carrier OFDM receiver, comprising:
 an OFDM demodulator for demodulating a multi-carrier signal to a demodulated multi-carrier signal, wherein the multi-carrier signal comprises a plurality of sub-carriers;   an ICI detector estimating an ICI strength of ICI from the demodulated multi-carrier signal when a system performance is less than a system performance threshold; and   an ICI canceller substracting the estimated ICI included in the received multi-carrier signal from the demodulated multi-carrier signal when the system performance is less than the system performance threshold.   
     
     
         14 . A multi-carrier OFDM receiver, comprising:
 an OFDM demodulator for demodulating a multi-carrier signal to a demodulated multi-carrier signal, wherein the multi-carrier signal comprises a plurality of sub-carriers;
 an ICI detector estimating an ICI strength of ICI from the demodulated multi-carrier signal; and 
 an ICI canceller substracting the estimated ICI included in the received multi-carrier signal from the demodulated multi-carrier signal when the ICI strength exceeds an ICI threshold.