G.165: Line Echo Canceller (LEC) Software
G.165: Line Echo Canceller (LEC) Software
GAO’s G.165, Line Echo Canceller (LEC) Software, cancels electrical line echoes caused by 2-to-4 wire conversion hybrids in telephone lines. The line echo canceller is also designed for integration with other software modules from GAO such as our DTMF Encoder/Decoder to enhance performance.
Line echo cancellation can be used in long distance voice communication, especially in links involving satellite networks and intercontinental long-haul circuits. It can also be employed in addition to echo suppressors for long delays. GAO’s line echo canceller consists of two user-callable functions that perform echo cancellation and initialization operations.
Features of Line Echo Canceller (LEC) Software - G.165
- Implemented in assembly or C.
- User-callable functions.
- Double-talk detection.
- Ideal for full-duplex operation.
- Compliant with the ITU-T G.165 recommendation.
G.168: Digital Network Echo Canceller
GAO’s Digital Network Echo Canceller (ITU-T G.168) software module is intended for use in the 4-wire portion of a circuit and is used for reducing the echo by digitally subtracting an estimated echo from the circuit echo. GAO’s G.168 echo cancellation software has the following fundamental requirements:
- Rapid convergence;
- Low returned echo level during single talk;
- Low divergence during double talk;
- Assured double talk detection;
- Proper operation during facsimile and low speed (9.6 kbit/s) voice-band data transmissions.
Features of Digital Network Echo Canceller (ITU-T G.168)
- Implemented in assembly or C.
- User-callable functions.
- Double-talk detection.
- Configurable echo tail length options: 8, 16, 32, 64 or 128 msec.
- Compliant with the ITU-T G.168 recommendation.
For ITU-T standard on G.165, click ITU-T, G.165 Standard.
For a complete list of GAO’s Telephony Software products, please see GAO’s Telephony Software.