Wireless technology continues to expand and diversify as consumer demand moves voice and data communications into fully mobile environments. Wireless is a significant growth area in the technology sector and a major research interest for TRLabs.
Autonomous wireless networks offer self-configuration and reliability advantages that are ideally suited for dynamic environments within the home, at work, or in the field (e.g., during emergencies). Work in this area is focused on system concepts, terminal synchronization techniques, modeling and performance of TCP in mobile ad hoc networks, and the design and simulation of robust routing protocols that support quality of service.
The objective of this research is to create viable techniques, methods and solutions essential to the standardization and eventual efficient implementation and deployment of the 4th generation (4G) systems, which are expected to occur after 2010. The emergence of 4G systems is seen as the final outcome of the current evolution of the 3rd generation (3G) cellular systems, which is currently under way. It will also involve considerable degree of integration of different types of wireless networks (cellular, wireless LANs, mobile and fixed broadband, and possibly satellite mobile) in the form of heterogeneous wireless networks. The research work currently under way encompasses areas such as multiple antenna techniques, multi-carrier transmission, radio link adaptation and adaptive radio resource allocation, as well as coordinated relaying for improved cellular coverage and capacity. The group also has considerable expertise and research experience in CDMA systems.
This research is targeted at developing novel multi-input multi-output (MIMO) systems that enhance system capacity, extend range, and mitigate interference. Major milestones include development of a 4x4 MIMO system operating at 5 GHz with 200 MHz of system bandwidth.
Several generations of software radio have been developed by TRLabs over the past several years; they have been used to facilitate the prototyping of various wireless projects. These radios are based on generic hardware that permits different channel modulation waveforms to be defined in software. The design of a fourth-generation software radio based on the latest DSP and FPGA hardware is now under development.
Ultra-Wideband (UWB) is an emerging technology for short-range, wireless personal area networks that provides the convenience and mobility of wireless communications to high-speed interconnections in the home and office. While several different UWB technologies are under investigation and/or development internationally, TRLabs research focuses primarily on impulse radio. Impulse radio offers a practical way of implementing UWB with reasonable tradeoffs between system capacity, complexity and robustness relative to competing UWB technologies. TRLabs is currently exploring several important research issues related to the design and implementation of impulse radio transceivers, including multi-path and narrowband interference mitigation and terminal synchronization.
The aim of this research is to develop a WLAN system that operates at over 1 Gbps using a combination of pre-equalization, antenna diversity, and frequency diversity at the base station with very simple terminals. Results to date include lab tests that show that a simple terminal with no signal processing can achieve data rates at up to 1.6 Gbps using these techniques. Work is proceeding on development of a fully functional prototype.