on frequencies below 500 KHz [3]. In the United States, one permits the use of up 1 Watt of power and a 15 meter long antenna between 160-190 KHz with no license requirement [4]. We can achieve 1.3-2 m communication with 6.78MHz and 13.56 MHz ISM bands, and 20-25m communication with 160-190 KHz LowFER bands even in wet clay underground with 1 Watt Tx power and the same MICA's antenna gain as shown in Figure 3(b) and 3(c). We currently configured two USRP nodes operating in low frequency such as 190 KHz ,6.78 MHz, and 13.56 MHz with two daughter boards (Basic Tx/RX and LFTX/RX) and Tri-band 7-inch omnidirectional vertical antenna (VERT400 antenna [5]).We will customize commercial low frequency antenna for subsurface monitoring applications and evaluate the performance of the system. To enhance the low frequency subsurface communication,we will also design experimental antennas which are compact and suitable for subsurface installation and compare their performance with commercial one. In the future, the performances(e.g.,received signal strength versus distance) of low frequency wireless signal networks with real underground communication system based on USRP platform