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Abstract-This paper presents a development of a wideband deltasigma modulator for fully digital GHz transmitters. The fully digital RF transmitter is developed as a promising solution for software defined radio (SDR) terminals and applications. The fully digital transmitter consists of a delta-sigma modulator, a highspeed multiplexer and a switching-mode power amplifier. The speed limitation of delta-sigma modulator is the main limitation to increase the signal bandwidth in fully digital transmitters. In this paper, the bandwidth of the fully digital transmitter is increased 8 times using parallel processing time-interleaved architecture, while maintaining the same signal quality. This architecture was implemented on FPGA and tested for different standards (WiMAX and LTE) with a signal bandwidth up to 8 MHz. The concept was assessed in terms of SNDR by using a differential logic analyzer at the output of FPGA, and the SNDR was found to be around 60 dB.

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We perturbed N=(2,2) supersymmetric WZW and sigma models on Lie groups by adding a term to their actions. Then by using non-coordinate basis we obtain conditions, from the algebraic point of view, under which the N=(2,2) supersymmetry is preserved. By applying this method, we have obtained conditions on the existence of N=(2,2) supersymmetry on the Drinfeld action (master action for the Poisson-Lie T-dual sigma models).