Adaptive Signal Processing in Wireless ATM and Other Asynchronous Packet Networks

无线ATM （Asynchronous Transfer Mode，异步传输模式）被提出用于下一代多媒体无线网络。无线环境下的ATM最初是针对高信噪比、宽带宽的信道而开发的，但它面临着无线信道时变的严峻挑战。无线ATM的成功在很大程度上取决于自适应接收机的设计，该接收机能够减轻时变信道的损害。本文主要研究异步时分多址（TDMA）网络中用于信道估计和均衡的自适应信号处理技术。调查的目的是探索新的方法，以尽量减少与训练信号的传输相关的开销。通过联合利用数据包的结构（如ATM小区）、介质访问控制协议和信号的时空分集，研究人员正在开发具有快速收敛速率和低功耗VLSI实现的新的信道估计和均衡算法。

Wireless ATM (Asynchronous Transfer Mode) has been proposed for the next generation multimedia wireless networks. Originally developed for channels with wide bandwidth at high signal-to-noise ratio, ATM in a wireless environment faces the difficult challenge that wireless channels are time varying. The success of wireless ATM, to a great extent, hinges upon the design of adaptive receivers that are able to mitigate time varying channel impairments. This research focuses on adaptive signal processing techniques for channel estimation and equalization in an asynchronous time division multiple access (TDMA) network. The objective of the investigation is to explore new approaches that minimize the overhead associated with the transmission of training signals. By exploiting jointly the structure of the data packet (e.g. ATM cell), the protocol of medium access control, and spatial-temporal diversities of the signal, the investigators are developing new channel estimation and equalization algorithms that have rapid convergence rates and low power VLSI implementation.