UHF communication link for MIMO SDR

Abstract

Aim of this project is to develop a UHF communication link for MIMO SDR, which can transmit real time video, audio and data from one node to another node through USRPs and RF front ends.. The purpose of the project was to make a prototype which could use modern techniques to efficiently enhance the communication quality and data rate. A system has been developed that is capable to communicate at higher data rates and with very less interference. MIMO system helps in achieving the target of higher data rate. 2x2 MIMO (Multiple Input Multiple Output) systems used in the test bed doubles data rate of information transfer as compare to conventional SISO (Single Input Single Output) systems. The requirement of efficient communication using bandwidth efficiently has increased. This need is fulfilled using OFDM (Orthogonal Frequency Division Multiplexing) as a modulation scheme. It incorporates FFT block which divides the whole available spectrum into sub-carriers. Cognitive technique is used for spectrum sensing. It allows users to find holes in the spectrum, and also detects that the spectrum is currently in use or free. This technique also allows user to use spectrum efficiently where the free bandwidth is utilized instead of being wasted. ZF VBLAST Detection is used for better detection of signals as compared to ZF detector. This communication model includes the use of MIMO-OFDM which is the basic need of a 4G technology. This prototype, radio link, can enhance the communication efficiency. The purpose of this test bed is to achieve those targets and take the communications carried out in military and civil industries to another level.