Beam Control System Design For Focused Arrays

Phased array,is a kind of beam-controlled array antenna composed of several independent antennas or radiation units.By controlling the amplitude or phase of each unit,a beam effect with advantages of high directionality,wide bandwidth and larger radiation range can be achieved.At present,most of the research on phased array beam control focuses on the far-field area of antenna radiation,and relatively little research is done on the near-field area.However,the research on controlling the beam in the nearfield region to achieve focus has a wide range of application prospects,and is in demand in scenarios such as RFID,wireless power transmission,biomedical thermal therapy,and food temperature detection.In practice,a beam control system is essential to achieve beam control.The wave control system completes the modulation of the RF components through digital signals,and then controls the whole phased array.Therefore,the focus of this paper is the design of the beam control system for focused arrays,and the following issues are studied.1.Near-field focusing algorithm design.In order to design the algorithm that can realize the near-field focusing effect and can be applied to the beam control system,firstly,the traditional focusing algorithm is proposed,and based on the existing theory,the focusing simulation is completed and the advantages and disadvantages of this algorithm are analyzed.Considering that the traditional focusing algorithm has the drawback that it cannot take into account the channel information and the actual cell radiation situation,the time inversion theory is introduced and an iterative time-inversion focusing algorithm is designed,which iteratively performs the time inversion process several times after the information of focusing position and focusing spot shape and size is given,and stops when the stable state is reached.Meanwhile,the iteration-based time inversion algorithm is performed in exponential form,which can complete the iteration in a short time and has the advantage of being fast and efficient.In order to visually test the performance of the algorithm,two sets of near-field focusing simulation experiments are also designed and completed in this paper.2.Beam control system design.In order to realize the focusing effect in practice,the wave control system design is completed based on FPGA.After completing the analysis of the resources required for functional implementation and the design of the overall implementation framework,we first design the peripheral circuits for the chip,including the power supply,configuration circuits and other parts,and then design and verify the program that can complete the functions of calculating the required phase of the focusing array and outputting the wave control code.Finally,the designed wave control system is tested in practice to verify its functional integrity.3.C-band phased array system implementation.In order to build the whole phased array system,the functional verification of the active transceiver component and the design of the focused microstrip antenna array as the transmitting antenna of the phased array were completed in turn.The functional verification of the phased array system composed of wave control system,active transceiver assembly and focusing array is also carried out.