Methods and apparatus for predicting voice quality in AMPS cellular radio systems
AssigneeNorthern Telecom Limited
InventorsClaude Royer, Charles P. Bernardin, Wing F. Lo
Life of this patent
Estimating the term…
Abstract
In methods and apparatus for assessing voice quality in AMPS cellular radio systems, a signal-to-noise ratio is estimated for a SAT signal of an RF channel, and the voice quality of the RF channel is inferred from the SAT signal-to-noise ratio.
Claims11
A method for assessing voice quality for an RF channel in an AMPS cellular radio system, the method comprising:
- transmitting a SAT signal from a base station to a mobile unit served by that base station on the RF channel;
- receiving the SAT signal at the mobile unit;
- retransmitting the received SAT signal at the mobile unit on the RF channel;
- receiving the retransmitted SAT signal at the base station;
- filtering the received SAT signal to separate frequency components at each possible SAT frequency;
- and
- comparing the separated components to estimate a signal-to-noise ratio for the received SAT signal at the base station.
A method for estimating a carrier-to-interference ratio of an RF channel in an AMPS cellular radio system, the method comprising:
- transmitting a SAT signal from a base station to a mobile unit served by that base station on the RF channel;
- receiving the SAT signal at the mobile unit;
- retransmitting the received SAT signal at the mobile unit to the base station on the RF channel;
- receiving the retransmitted SAT signal at the base station;
- estimating a signal-to-noise ratio for the retransmitted SAT signal received at the base station;
- and
- calculating a carrier-to-interference ratio for the RF channel from the estimated signal-to-noise ratio.
A method for estimating a carrier-to-interference ratio of an RF channel in an AMPS cellular radio system, the method comprising:
- transmitting a SAT signal from a base station to a mobile unit served by that base station on the RF channel;
- receiving the SAT signal at the mobile unit;
- retransmitting the received SAT signal at the mobile unit to the base station on the RF channel;
- receiving the retransmitted SAT signal at the base station;
- filtering the retransmitted SAT signal received at the base station to separate frequency components at each possible SAT frequency;
- and
- comparing the separated components to estimate the signal-to-noise ratio for the retransmitted SAT signal received at the base station;
- and
- calculating a carrier-to-interference ratio for the RF channel from the estimated signal-to-noise ratio.
Apparatus for assessing voice quality of an RF channel in an AMPS cellular radio system, the apparatus comprising:
- a receiver for receiving a signal on an RF channel;
- a filter network for filtering the received signal to separate frequency components at each possible SAT frequency;
- a power measurer for measuring powers of the separated frequency components;
- and
- a comparator for comparing the measured powers to estimate a signal-to-noise ratio.
Dependencies are inferred from the claim text.