Theoretical Analysis And Study Of Digital Phased Antenna

With the social development, technological progress, the need for long-distance communication antenna gain higher and higher, a plurality of antenna arrays can effectively increase the size of the antenna power, provides higher gain. Phased array antennas are arranged by the radiating element made of a directional array antenna, so that it can scan in any spatial direction. Phased array antenna has a flexible beam pointing, and can be able to scan any direction quickly. Also it is able to adapt to a variety of complex work environment, and has a good anti-jamming. But the phased array antenna device are complicated and expensive. In this paper we propose a new sampling method, by a simple control switch instead of the phase shifter to change the phase of realization of the role, which can greatly reduce the cost of array antennas. In this paper we did the following aspects:We research on the digital phased array antenna, electromagnetic interference, the principle of superposition pattern multiplication theorem and the array factor characteristics. We study the linear phased array scanning theory and planar phased array antenna scanning theory, focuse on studying its work mechanisms.Second, on the basis of the phased array antenna we propose a new sampling algorithm by controlling switch to change the phase. Due to the different position, each signal received by antenna has a relative phase difference. By our sampling algorithm the system can be simplified. By weighted combining received signals, we can form a main beam in the direction of the desired signal, thereby increasing the output signal of noise ratio. Meanwhile, we theoretically derive the sampling methods in the time domain and frequency domain, and give the traditional phased array radiation pattern and sampling methods figure.Finally, after proving the feasibility of sampling methods in theory, we set up the simulation environment, simulate the sampling methods we proposed in linear phased array and planar phased array, and give detailed descriptions of function and parameter setting data of each module. And we compare and analyse results obtained in different angles, different pitch conditions. Simulation results show that the proposed sampling method basically can change the phase of action to achieve a directional scanning array antenna, while significantly reducing costs.