초록 ▼

A method and apparatus for improving the signal-to-noise ratio of low-magnitude input signals that coincide with a noise band of channel noise introduced into the transmission of data across a communication channel. A transmitting and receiving modem establish a communication channel for facilitatin

A method and apparatus for improving the signal-to-noise ratio of low-magnitude input signals that coincide with a noise band of channel noise introduced into the transmission of data across a communication channel. A transmitting and receiving modem establish a communication channel for facilitating the exchange of input signals. The receiving modem evaluates the noise spectrum of the communication channel on a dynamic basis at the commencement of the exchange of information. The transmitting modem suspends transmission while the receiving modem evaluates the noise band and magnitude of the noise information. The channel noise band and levels are transmitted from the receiving modem to the transmitting modem to generate pre-compensation modulation points that have an enhanced magnitude outside the channel noise. The enhanced low-magnitude input signal and all other signals are propagated across the communication channel and exposed to the channel noise. The signal-to-noise ratio of the low-magnitude signal is improved due to the magnitude enhancement of the susceptible signals prior to transmission.

대표청구항 ▼

[ What is claimed and desired to be secured by United States Letters Patent is:] [1.] In a communication system having a transmitting modem interconnected with a receiving modem via a communication channel exhibiting channel noise in a channel noise band, a method for improving the signal-to-noise r

[ What is claimed and desired to be secured by United States Letters Patent is:] [1.] In a communication system having a transmitting modem interconnected with a receiving modem via a communication channel exhibiting channel noise in a channel noise band, a method for improving the signal-to-noise ratio of low-magnitude input signals occurring in said channel noise band, said method comprising the steps of:(a) said receiving modem listening to channel noise on a communication channel;(b) determining both channel noise band of said channel noise introduced by said communication channel and compression level information to increase the magnitude of said low-magnitude input signals beyond the magnitude of said channel noise;(c) notifying a transmitting modem of said channel noise band and said compression level information;(d) enhancing through said transmitting modem said low-magnitude input signals occurring in said channel noise band according to said compression level information by boosting a magnitude of quadrature amplitude modulation constellation points occurring in said channel noise band that represent said low-magnitude input signals according to said compression level information to form enhanced low-magnitude signals as transmitted to said receiving modem; and(e) reducing both said enhanced low-magnitude signals to approximate said low-magnitude input signal as presented to said transmitting modem and said channel noise introduced by said communication channel.