Transmit beamformer design with a PAPR constraint to tradeoff between beampattern shape and power efficiency Abstract   This study examines the effect of peaktoaverage power ratio (PAPR) constraint on the transmit beamformer design problem with the goal of establishing a tradeoff between the power efficiency (maximizing the average transmitted power) and other metrics such as the power level fluctuation in mainlobe, peaksidelobe level (PSL), etc. Typically, unimodular weights are utilized in transmitbeamforming to maximize the average transmitted power. Yet, unimodular weights maximize the power efficiency at the expense of other performance metrics. It is shown that even a slight relaxation of the design problem from the unimodular condition (PAPR       1   ), say setting PAPR     xe2xa9xbd  1.1   , results in a significant improvement in other performance metrics at a negligible loss of power efficiency. To achieve the tradeoff between the metrics, an alternating direction method of multipliers (ADMM) based solution to the transmit beamformer design is given. The suggested solution is applicable to both narrowband and wideband beamformers and also to some other related problems such as the unimodular radar waveform design (code design) problem.

Constrained Transmit Beampattern Design Using a Correlated LFMPC Waveform Set in MIMO Radar This paper considers the design of a desired transmit beampattern under the good ambiguity function constraint using a correlated linear frequency modulationphase coded (LFMPC) waveform set in multipleinputmultipleoutput (MIMO) radar. Different from most existing beampattern design approaches, we propose using the LFMPC waveform set to conquer the challenging problem of synthesizing waveforms with constantenvelope and easygeneration properties, and, meanwhile, solve the hard constraint of a good ambiguity behaviour. First, the ambiguity function of the LFMPC waveform set is derived, and the superiority of LFMPC waveforms over LFM and PC waveforms is verified. The temporal and spatial characteristic analysis of the LFMPC waveform set demonstrates that both the transmit beampattern and sidelobe level are mainly affected by the frequency intervals, bandwidths, and phasecoded sequences of the LFMPC waveform set. Finally, the constrained beampattern design problem is formulated by optimizing these parameters for desired beampatterns and low sidelobes at different doppler frequencies, which is a biobjective optimization problem. To solve this, we propose a joint optimization strategy followed by a mandatory optimization, where the sequence quadratic programming (SQP) algorithm and adaptive clonal selection (ACS) algorithm are exploited iteratively. The simulation results demonstrate the efficiency of our proposed method.