EXTENDED BANDWIDTH ADAPTIVE DIGITAL PRE-DISTORTION WITH RECONFIGURABLE ANALOG FRONT-ENDS

摘要

A pre-distortion method. A signal to be transmitted Tx is pre-distorted to compensate for nonlinearities of a transmitter. The pre-distorted signal is filtered by an EBEE filter and a baseband filter. The EBEE filter has a filter characteristic of that cancels the baseband filter response over the range of frequencies from a first corner frequency of the baseband filter to a frequency of N*fB where N is a highest order of distortion component being cancelled and fB is the bandwidth of the original signal to be transmitted. This abstract is not to be considered limiting, since other embodiments may deviate from the features described in this abstract.

主权项

1. A pre-distortion method of correction of radio transmitter nonlinearity, comprising:
characterizing the transmitter nonlinearity as a distortion function D(v), where v is an amplitude of the signal to be transmitted, and where the distortion components to be corrected are determined by the order of nonlinearity N to be corrected by the system; receiving a signal to be transmitted Tx(f) having a maximum significant frequency component at frequency fTX; using a pre-distorter having a transfer function DPRE(v) that models a distortion characteristic to produce a pre-distorted signal TxPRE(f)=DPRE(Tx(f)); filtering the pre-distorted signal TxPRE(f) with an Effective Bandwidth Enhancement Equalizer (EBEE) filter to produce a filtered pre-distorted signal TxE(f); passing the filtered pre-distorted signal TxE(f) through a baseband filter having filter characteristics BB(f) to produce a signal corrected signal for transmission TxC(f)=TxE(f)*BB(f), where the EBEE filter has a filter characteristic of HE(f), where HE(f)*BB(f) approximately equals 1 over the range of frequencies from a first corner frequency fC of BB(f) to frequency N*fTX; up-converting the signal TxC(f) to radio frequency for transmission; and transmitting the up-converted signal TxC(f) at radio frequencies.