The DOA Estimation using the Low Cost DBF Array Antenna

In Recent years, the digital signal processing has progressed remarkably. Development of the digital beam forming (DBF) array antenna is necessary for the future mobile communication systems. The DBF array antenna realizes beam operation with appropriate weight in each element by using digital signal processing. Therefore, the DBF array antenna is investigated by many researchers. However the DBF array antenna is very complex and expensive, because its hardware configuration consists of circuits by ASICs or FPGAs [1] [2]. In our study, we suggest the low cost DBF array antenna [3], which consists of simple components such as a personal computer, an A/D converter board and a low cost RF module. By using this DBF array antenna system, we are examining various types of algorithms. For example, we are implementing an algorithm that enables the estimation of both the direction of arrival (DOA) and the time of arrival (TOA), because angular spread and delay spread are very important factors in an adaptive array antenna. In this paper, the DOA is measured by using the proposed system in anechoic chamber. In addition, we rotate the antenna elements around the center element to increase the number of the elements virtually, and then it can improve the resolution of DOA.