Proceedings with Extended Abstracts (single PDF file) - Radio ...

Figure 1: Configuration of a high-gain antenna and the sub-array.3 Application to High Gain ArraysHere we consider the application of DCMP-CN to the case of a high-gain antenna array consistingof several hundred elements. In such a case, it is not practical to control all of the elements.Instead, we select several antennas at the outer edge of the array to configure a sub-array, andonly control the weights of its elements as shown in Fig. 1, keeping the weight of the main arrayoutput to 1. In the radar application, the main array is used both for transmission and reception,and the sub-array is used only for reception. This configuration is useful in suppressing theclutter echoes of existing radar by adding several receiving antenna elements. In this case, theoutput power is rewritten asÈ ÓÙØ ½ ¾ Ï À Ê ÜÜ Ï ½ ¾´Ü ½Ü £ ½ · Ï À ¾Ò ¾Ò Ü £ ½ · Ü ½ À ¾ÒÏ ¾Ò · Ï À ¾Ò Ê ÜÜ Ï ¾Ò µ (10)where subscript 1 denotes the output of the main array, and 2 to Ò correspond to sub array.Since the constraints are given only to the sub-array elements, the problem is expressed asÈ ÓÙØ ¾´Ü ½ ½Ü £ ½· Ï¾Ò À ¾Ò Ü £ ½· Ü ½ ¾ÒÏ À ¾Ò · Ï À ¾ÒÊ ÜÜ Ï ¾ÒÑÒÏThe cost function is then given by×ÙØ ØÓ Ì ¾ÒÏ £ ¾Ò À ² Ï À ¾ÒÏ ¾Ò Í (11)É ´Ï µ ½ ¾´Ü ½Ü £ ½ · Ï À ¾Ò ¾Ò Ü £ ½ · Ü ½ À ¾ÒÏ ¾Ò · Ï À ¾Ò Ê ÜÜ Ï ¾Ò µ· ´Ï À ¾Ò ¾Ò Àµ´ À ¾ÒÏ ¾Ò À £ µ·´Í Ï À ¾ÒÏ ¾Ò µ ¾ (12)4 Observations438We applied this algorithm to the data taken with the MU (Middle and Upper Atmosphere)radar. It is a large atmospheric radar with a flexible active phased array antenna consistingof 475 Yagi-Uda antennas. The antenna array consists of 25 groups of hexagonal sub-arraywith 19 crossed 3-element Yagi antennas. A transmit/receive module is connected to each Yagiantenna. On reception, RF signal of 46.5 MHz is converted to IF of 5 MHz at each module, andthe output of 19 modules are combined at each group. Combined IF signals from 25 groups