Initial Set-up of a Joint UK-China Open Access Testbed

Visiting researcher: Dr Jian Sun (SDU)
Host researcher: Dr Cheng-Xiang Wang and Dr Xuemin Hong (HWU)
Duration: 3 months
Status: Completed
 

Biography of the visiting researcher

Dr. Jian Sun received his BSc and MEng degrees in Electrical Engineering from Zhejiang University, China, in 1996 and 1999, respectively. He worked as a software engineer for an Intelligent Transport System for half a year. He received his PhD degree in Communication and Information System from Zhejiang University in 2005. He then became an Assistant Professor in the School of Information Science and Engineering, Shandong University. He was a visiting scholar at University of California, San Diego, from August to December, 2008. His research interests include synchronization techniques for various communication systems, especially multicarrier, multi-antenna and multiuser system, cognitive radio, embedded system design and application, and implementation of communication system on reconfigurable devices.
 

Background and motivation

Many advanced wireless communications technologies for (B)4G systems have been extensively evaluated via simulations. To further validate these technologies in real-world scenarios, a flexible testbed supporting rapid prototyping of wireless systems is needed. A key mission of the UC4G project is to build a UK-China open access testbed to allow joint research outcomes to be further evaluated and demonstrated. After several discussions, a consensus was reached to build the UC4G testbed in two stages. The first stage is to build a small-scale link-level (single transmitter, single receiver) testbed at Heriot-Watt University (HWU). This testbed should be research-friendly and useful enough to allow rapid demonstration of some new technologies. The second stage is to link the HWU testbed with other (possibly large-scale) testbeds in the UK and China, such as the SWAN testbed in Shanghai Research Centre for Wireless Communications.
 
Baseband signal processing will be supported by a hybrid hardware platform including two types of hardware: filed-programmable gate array (FPGA) and multiple general purpose processors (GPPs). The FPGA is used as an “inner transmitter/receiver” to interface with high-sample-rate intermediate frequency (IF) signals and perform initial signal processing (e.g., OFDM modulation and demodulation), while the GPPs are used as an “outer transmitter/receiver” to process lower-sample-rate baseband signals and perform more complicated signal processing (e.g., multiple-input multiple output (MIMO), channel decoding).
 
With the above architecture, wireless algorithms will be partitioned and implemented on either GPPs or FPGAs. Implementation on GPPs is similar to computer-based simulation and therefore easy to be adopted by most wireless researchers. In contrast, implementation on FPGA requires different set of hardware programming and engineering skills, which is not owned by most wireless researchers. Without prior experience, implementation on FPGA can be time and resource consuming. Fortunately, most algorithms to be implemented on the FPGA are mature technologies, allowing a standard inner receiver to be built without the need of frequent further modifications. It is also possible, with minimum amount of time and efforts, to “transplant” an established FPGA-design to the HWU testbed.
 
The research team at SDU has devoted a few years to develop a FPGA-based, real-time MIMO-OFDM system. The system has been successfully tested in real-world scenarios. The main aim of this visiting proposal is to transplant the FPGA-based inner receiver at SDU to the HWU testbed. As a result, the HWU testbed will become a truly research-friendly platform, providing a standard, real-world, high-speed baseband interface for future researchers to test their advanced algorithms solely based on GPPs.
 

Research activities

  1. To transplant the SDU MIMO-OFDM inner receiver to the HWU testbed.
  2. To benchmark the performance of the transplanted system.
 

Outcomes

  1. Have implemented a real-time SISO-OFDM WLAN transmtter - reciever link on the NI-based testbed.
  2. Have implemented a real-time MIMO-OFDM WLAN transmtter - reciever link on the NI-based testbed.
Powered by Drupal, an open source content management system