Performance Enhancement of DS-UWB Short Range Communication System Using Equalization Techniques

Abstract

UWB is a major research area in the field of wireless communication. The IEEE 802.15.3a has been assigned the job of standardizing it. It is being considered as a breakthrough technology capable enough to revolutionize short range wireless communication. Ultra wideband communication as its name implies has large absolute bandwidth greater than 500 MHz and operating frequency band is 3.1 GHz- 10.6GHz. It is a rapidly growing technology that plays a very promising role in modern age wireless communication. It finds application in various sectors, for example in medical application to observe the status of patient using wireless health monitoring of life sustaining systems. In vehicular technology it can be used for obstacle avoidance and fast data transmission, and in military application as radar for detection behind walls and other blockages. Since it is based on short pulse carrier less transmission so hardware implementation becomes less complex and cheap. Thesis work has been done to study the BPSK modulation based DS-UWB communication system. Direct sequence spread spectrum (DSSS) technique along with UWB signal and two types of equalization techniques has been incorporated to mitigate the multipath fading effect associated with S-V indoor channel. Rake receiver has been used to utilize the energy of various delayed multipath components to improve the performance of the system. In short range communication process, indoor channel model or UWB channel model has been studied with different transmitter receiver separation, using some fundamental parameters of channel. Inter symbol interference (ISI) is a major problem in frequency selective fading channels, to overcome this problem, RAKE-MMSE equalizer and single carrier frequency domain equalizer (SC-FDE) have been incorporated. Thesis comprises of the system performance study and design done by using the above said equalization techniques for DS-UWB communications system.