Method and apparatus for automatic compensation of signal losses from transmission over conductors

摘要

A method and apparatus for automatic compensation of insertion loss in signals transmitted over conductors is presented. The present invention is particularly applicable to the transmission of signals over long lengths of CAT-5 or similar twisted-pair cables. A reference signal having a known form and strength (e.g. a pulse signal) is provided to each pair of conductors carrying a component of a signal from a transmitter to a receiver. The receiver includes adjustable gain amplifiers for each conductor pair over which a component of the signal is transmitted. The gains of the amplifiers are initially set at an initial level (e.g., their maximum gain) to allow detection of the reference signal. Once the reference signal is detected in a conductor pair, the amplifier gains are adjusted such that the level of the reference signal is restored approximately to its original form and strength.

主权项

1. A method for automatic compensation of losses in a signal transmitted over conductors and received by a receiving apparatus comprising:
receiving by said receiving apparatus of an input signal over a conductor, said input signal comprising a reference signal; generating by said receiving apparatus an output signal from said input signal by applying compensation to said input signal, wherein said applying said compensation comprises: applying an initial amount of compensation by compensation circuitry of said receiving apparatus, said compensation circuitry configured to produce a variable amount of compensation up to a maximum amount of compensation, wherein said initial amount of compensation comprises said maximum amount of compensation; measuring a current level of said reference signal in said output signal; comparing said current level of said reference signal to a first level; and adjusting an amount of compensation applied by said compensation circuitry to said input signal until said current level of said reference signal is approximately equal to said first level.