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What is the Mu-Law PCM voice coding standard used in North American T-Carrier telecommunications transmission systems? June 8, 2009

Posted by HubTechInsider in Definitions, Telecommunications, VUI Voice User Interface.
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Sampling and 4-bit quantization of an analog s...

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Mu-Law encoding is the PCM voice coding standard used in Japan and North America. It is a companding standard, both compressing the input and expanding the data upon opening after transmission. Mu Law is a PCM (Pulse Code Modulation) encoding algorithm where the analog voice signal is sampled eight thousand times per second, with each sample being represented by eight bits, thus yielding a raw transmission rate of 64 Kps. Each sample consists of a sign bit, a three bit segment which specifies a logarithmic rqange, and a four bit step offset into the range. The bits of the sample are inverted before transmission. A Law encoding is the voice coding standard which is used in Europe.

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What is a LATA, in the telecom sense? May 4, 2009

Posted by HubTechInsider in Telecommunications.
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Map of the LATA boundaries for the US. Created...

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lataIn 1984, in conjunction with Divestiture, the Justice Department created local access and transport areas (LATAs). LATAs define the contiguous geographic areas in which local Bell telephone companies were allowed to sell local and long distance services. Interexchange carriers and competitive local exchange carriers (CLECs) carried calls between the 197 LATAs. States with small populations, such as Maine, Alaska, and Wyoming, are made up of one LATA. Thus, Qwest (formerly US West), the Bell company serving Wyoming, are made up of one LATA. Thus, Qwest (formerly US West), the Bell company serving Wyoming, was allowed to provide long distance to all sites within Wyoming. California has eleven LATAs, and New York State has eight. Calls between LATAs in California were handed off to interexchange carriers, as were those between LATAs in New York State.
Now that RBOCs have Federal Communications Commission (FCC) permission to sell inter-LATA long distance, much of the concept of LATAs has lost significance except for billing. Telephone companies often rate their intrastate intra-LATA and intrastate inter-LATA calls differently.lata

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