Performance enhancement of first order three-level envelope delta sigma modulator based transmitter

This work is concerned with the analysis, based on MATLAB simulation, of 1^st and 2^nd order Multi-level envelope delta sigma modulators (EDSMs) that are used for high efficiency and linearity wireless mobile transmitter architectures with an Orthogonal Frequency Division Modulation (OFDM) signal and long term evolution (LTE) signal. The analysis is based on measuring the linearity and the efficiency of the three-level EDSM. It was shown that, at different input signal power levels of the three-level EDSM, 1^st order three-level EDSM is able to achieve a performance that is close to the performance of the 2^nd order counterpart. While 1^st order DSM requires less circuitry, it is recommended to employ 1^st order three-level EDSM instead of using 2^nd order three-level EDSM. 1^st order three-level EDSM has a signal to noise distortion ratio (SNDR) and coding efficiency of 58 dB and 77%, respectively. While 2^nd order three-level EDSM showed SNDR of 61.5 dB and coding efficiency of 76.4%. Also, with a long term evolution (LTE) signal, the 1^st order EDSM has better performance, in terms of SNDR and CE, than that of the 2^nd order EDSM circuit.