High-precision Direction Finding Based on Time Modulation Array with Single Radio Frequency Channel and Composite Baselines
With the rapid developments of positioning systems,high-precision and low-cost direction-finding technologies are urgently needed.The hardware complexity and economic cost of traditional direction-finding methods have hindered their wide applications.Recently,direction finding based on Time-Modulated Arrays(TMAs)has overcome the shortcomings of traditional direction-finding methods.Nevertheless,to ensure measurement accuracy,one has to keep an adequate number of array elements in common TMAs.Consequently,a question arises,i.e.,is it possible to reduce the number of array elements in TMAs,thus making the hardware complexity as low as possible?A novel direction-finding method based on the TMA with a single radio frequency channel and composite baselines is proposed in this paper.In the method,four antennas are meticulously arranged at specific intervals to form double-long baselines,and accurate and low-cost direction finding is realized with the ingenious usage of Field Programmable Gate Array(FPGA)and single receiving channel.To verify the effectiveness of the method,a prototype system in the S band is designed,fabricated,and measured.Detailed comparisons with the existing methods are provided.The work will benefit the development and application of high-precision and low-cost direction-finding systems.
Direction findingSpectrum harmonic analysisTime-modulated arrayAntenna array
万方数据
维普
