Research On Wideband Digital Array Receiving Channel Equalization

With the increasingly heavy task of space TT&C,the traditional single target aperture antenna measurement and control can not meet the demand.As a research hotspot in radar communication,wideband digital array can meet the needs of multi-target measurement and control.The wider the work bandwidth,the greater the amount of information transmitted per unit time.The broadband digital array contains hundreds or thousands of access channels.The forward shift of the digital end has reduced the number of simulators,but the most important TR component of the transceiver is still irreplaceable.The existence of analog devices inevitably makes the amplitude and phase characteristics of each channel different.The inconsistency of channels will have a serious impact on the performance of the array beamforming,and the balance of the broadband mismatch channel is also a probiem that must be solved before the array antenna work.Aiming at this problem,we first analyze the influence of channel mismatch on the performance of domain equalization algorithm based on FIR transverse filter,and the optimal equilibrium parameters are found out under the different parameters.Secondly,the algorithm of frequency domain equalization is improved.In view of the discontinuity of frequency band in direct truncation band,the characteristic of quasi band amplitude frequency is proposed,which avoids the shortcoming of direct truncation of frequency points and improves the performance of equilibrium.Considering that the High-tap filter needs more orders in the balanced high-order distortion mismatch channel that is based on the FIR filter.The Laguerre filter should be further optimized in the later stage.Finally,combining the parameters of the specific broadband receiver,by adding the amplitude and phase characteristics of the mismatched channel to the intermediate frequency end,it is more close to the actual situation receiving channel mismatch model.After comparing the two calibration signals of BPSK and LFM signals,the latter is more suitable as the input of the frequency domain equalization algorithm.The influence of 8 bit,16 bit and 32 bit fixed_point quantization on frequency domain equalization is simulated.It is concluded that 16 bit fixed-point quantization can meet the requirement of equalization performance.Finally,the adaptive Frost beamforming and equalization filters are combined together,and space resampling is used to simplify the structure and reduce resource consumption.