CDMA Glossary T-Z

Timer-Based Registration

A registration method in which the mobile station registers whenever a counter reaches a predetermined value. The counter is incremented an average of once per 80 ms period.

Time Reference

A reference established by the mobile station that is synchronous with the earliest arriving multipath component used for demodulation.

TOLR

See Transmit Objective Loudness Rating.

Traffic Channel

A communication path between a mobile station and a base station used for user and signaling traffic. The term Traffic Channel implies a Forward Traffic Channel and Reverse Traffic Channel pair. See also Forward Traffic Channel and Reverse Traffic Channel.

Transmit Objective Loudness Rating (TOLR)

A perceptually weighted transducer gain of telephone transmitters relating sound pressure at the microphone to voltage at a reference electrical termination. It is normally specified in dB relative to one millivolt per Pascal. See IEEE Standard 269-1992, IEEE Standard 661-1979, ITU-T Recommendations P.76 and P.79.

Transcoder

A device that transforms signals from one type of digital representation to another.

Unique Challenge-Response Procedure

An exchange of information between a mobile station and a base station for the purpose of authenticating the mobile station identity. The procedure is initiated by the base station and is characterized by the use of a challenge-specific random number. Cf. Global Challenge Procedure.

Visited System

The cellular system that is providing service to a roaming mobile station.

Visitor Location Register (VLR)

The database used by a visited system to maintain information about recently-served roaming subscribers.

Voice Privacy

The process by which user voice transmitted over a traffic channel is afforded a modest degree of cryptographic protection against air-interface eavesdropping.

Walsh Function, or Walsh Code

One of a set of orthogonal waveforms, based on the Walsh-Hadamard matrices. Walsh functions are used for two purposes in CDMA. In the forward link they are used as orthogonal cover to create independent transmission channels. In the reverse link they are use as orthogonal modulation.

Zone-Based Registration

An autonomous registration method in which the mobile station registers whenever it enters a zone that is not in the mobile station's zone list.