Adaptive Frame Structure for Broadband Mobile Multihop Wireless System
The frame structure design is more challenging in the new mobile multihop relay based (MMR) network architecture, as numerous dimensions of design constraints and challenges have been introduced therein. In this project, we proposed an adaptive frame structure to meet the challenges of a mobile multihop relay based network.
Background & Objective: The new IEEE 802.16j standard was created to help to resolve problems like limited coverage and terminal transmit power of the IEEE 802.16e standard. In this project, our objective is to develop an adaptive frame structure that is simple yet flexible and one which enables multihop operation while still maintaining the backward compatibility with the legacy mobile stations of IEEE802.16e.
Technical Discussion: Similar to the legacy design, the new frame structure for MMR network is also composed of a DL (Down Link) and an UL (Up Link) portion. However, in order to enable multihop communication, the DL and UL subframe is further divided into multiple zones in the time domain. As depicted in the Figure, the first zone in both the DL and UL subframe is dedicated for communication that directly engages MSs (Mobile Stations), and thus is naturally called the access zone. The access zone in both DL and UL may be followed by one or multiple relay zones. In each relay zone, BS (Base Station) and RS (Relay Station) can stay in the mode of transmission, reception or being idle. The number of relay zone in the DL sub-frame “n†may or may not be equal to the number of relay zone in the UL sub-frame “mâ€. When “n†and “m†equal to zero, it implies that the frame structure becomes the frame structure of the 802.16e standards. The duration of both the access and relay zone are flexible as long as they are confined within the duration of the sub-frame.
Future Direction: To develop an adaptive frame structure that can more effectively deal with real time signal and data simultaneously.
Contacts:
Koon Hoo Teo
Jinyun Zhang
Technology Area: Digital Communications
Modification Date: October 2, 2007
