Communication electronics for telephony and internet access

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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.