Communication electronics for telephony and internet access

首先提出的工作是改进宽带频域反射计（FDR）方法由以前的学生开发。这种方法将使电话公司更容易识别和定位电话线中干扰互联网接入的障碍物。测量反射角的新功能可以帮助描述故障，便于在电缆进水等紧急情况下快速修复。在SaskTel（北美第一个商用高速互联网）的帮助下，TRLabs完成了这一开发。一家加拿大公司（www.consultronics.com）已经将软件FDR集成到他们的顶级仪器中，并计划实现一个功能更强大的硬件版本。第二个提议的工作应用扩频同步器，由以前的学生建立在VLSI芯片，以解决911蜂窝电话定位问题。美国最近的法规引发了相当多的研究，并对GPS技术进行了很多考虑。在建筑物内，一些卫星信号降低了几个数量级，在存在高热噪声和来自其他卫星的全强度信号的情况下难以探测。我们预计我们的同步器将能够实现这一目标。第三种建议使用相同的VLSI同步器，旨在将分组传输的效率与码分多址（CDMA）的效率结合起来。目前的分组码分多址研究假定对基本的码相同步有冗长的序言。我们建议消除数据包序言，因为我们的同步器可以在数据调制和多普勒频移的存在下工作。

The FIRST proposed work is to refine the wideband frequency domain reflectometer (FDR) method developed by former students.  This method will allow telephone companies to more easily identify and locate obstructions in telephone lines that interfere with Internet access. The new capability of measuring reflection angle can help characterize the fault and facilitate rapid repair in urgent cases such as water in the cable. This development has been done at TRLabs with the help of SaskTel (first in North America with commercial high-speed Internet). A Canadian company ( www.consultronics.com) has incorporated software FDR in their top-of-the-line instrument and plans to implement a much more capable hardware version. The SECOND proposed work applies a spread spectrum synchronizer, built in a VLSI chip by former students, to the problem of 911 cellular telephone location finding. Recent US regulations have triggered considerable research and there has been much consideration of GPS technology. Within buildings, some satellite signals are reduced by several orders of magnitude making detection difficult in the presence of high thermal noise and full-strength signals from other satellites. We anticipate that our synchronizer will be capable of meeting this objective. A THIRD proposed work uses the same VLSI synchronizer and aims to combine the efficiency of packet transmission with the efficiency of code division multiple access (CDMA). Current research on packet CDMA assumes a lengthy preamble for the essential codephase synchronization.  We propose to eliminate the packet preamble since our synchronizer can operate in the presence of both data modulation and Doppler shift.