Coded Diversity Combining and Channel Estimation for Wireless Data Communications

无线数据通信的编码分集组合和信道估计

• 批准号: 9706592
• 负责人: Zygmunt Haas
• 金额: --
• 依托单位: Cornell University
• 依托单位国家: 美国
• 项目类别: Continuing grant
• 财政年份: 1997
• 资助国家: 美国
• 起止时间: 1997-09-01 至 2001-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9706592&HistoricalAwards=false
• 关键词: Coded; Diversity; Combining; Channel; Estimation

Recently, a new post-detection macrodiversity scheme was proposed for cellular communication systems. In this new scheme, termed Multiply-Detected Macrodiversity (MDM), the signals at multiple base stations are detected and used as input to a Decision Algorithm, which provides an optimal decision of what was transmitted. The MDM scheme shows considerable improvement in the Bit-Error Rate (BER), especially when the mobile is close to the boundary between cells. As the boundary between cells is exactly the region in which the quality of the mobile's signal is mostly impaired, the MDM scheme has the effect of equalizing the BER throughout the system coverage area. The Decision Algorithm of the MDM scheme requires as an input, in addition to the separate detections of the receivers, also an estimation of the quality of the received signals, so that appropriate"weightings" of these signals can be applied in the post-detection combining process. To obtain estimates, usually some sort of channel measurement is performed; e.g., the signal power (S-diversity) or the Signal-to-Interference-Ratio (S/I-diversity). In such cases, the measurement process complicates the design of the transmitter/receiver hardware and the operation of the system. Furthermore, the measurements are subject to high variance and need to be averaged over time. To avoid the disadvantage of the measurement-based quality of signal estimation, we propose here to investigate the use of channel coding to evaluate the transmission characteristics of a wireless channel for macrodiversity reception. The proposed channel estimation schemes use side information generated during the decoding process.In summary, we intend to study the use of the MDM combining with coded channel estimation in the case of a single site equipped with multiple,widely-separated receivers and in the case of multiple cell sites. In the latter case, we will investigate the use of both post-detection and predetection combining (with quantization of the recei ved signal), comparing the performance in the schemes in the presence of channel impairments characteristic to the mobile communication environment.

最近，针对蜂窝通信系统提出了一种新的检测后宏分集方案。在这个称为多重检测宏分集（MDM）的新方案中，检测多个基站的信号并将其用作决策算法的输入，该算法提供了传输内容的最佳决策。 MDM 方案在误码率 (BER) 方面显示出相当大的改进，特别是当移动设备靠近小区边界时。由于小区之间的边界正是移动设备信号质量最受影响的区域，因此MDM方案具有均衡整个系统覆盖区域的BER的效果。 MDM方案的决策算法除了需要对接收器进行单独检测之外，还需要对接收信号的质量进行估计作为输入，以便可以在检测后组合过程中应用这些信号的适当“加权”。为了获得估计，通常会执行某种信道测量；例如，信号功率（S 分集）或信号干扰比（S/I 分集）。 在这种情况下，测量过程使发射器/接收器硬件的设计和系统的操作变得复杂。此外，测量结果存在很大差异，需要随时间进行平均。 为了避免基于测量的信号估计质量的缺点，我们在此建议研究使用信道编码来评估宏分集接收的无线信道的传输特性。所提出的信道估计方案使用解码过程中生成的辅助信息。 总之，我们打算研究在单个站点配备多个、广泛分离的接收器的情况下以及在多个小区站点的情况下，将 MDM 与编码信道估计结合使用。在后一种情况下，我们将研究检测后和检测前组合（对接收信号进行量化）的使用，比较在存在移动通信环境特有的信道损伤的情况下方案的性能。