V.32

Important features of modems adhering to this standard are:

• Duplex mode of operation on generalized switched telephone networks and two-wire point-to-point leased circuits
• The data signaling rate implemented in the modem is 9.6 Kbps or 4.8 Kbps
• The 9.6 Kbps data signaling rate uses two alternative modulation schemes that employ 16 carrier states and use Trellis coding with 32 carrier states. Modems that use this data signaling rate will also be able to work together by using 16 state alternatives.
• Channel separation using echo cancellation techniques
• Quadrature amplitude modulation (QAM) for each channel with a synchronous line transmission of around 2,400 bauds
• Asynchronous mode of operation is optionally provided in accordance with recommendation V.14

Modems that adhere to the V.32 standard incorporate a full-duplex echo canceler data modem that supports data rates ranging from 14.4 Kbps down to 4.8 Kbps in steps of 2.4 Kbps. The modulation methods adopted are quadrature phase-shift keying for 4.8 Kbps and QAM for the other data rates. The Trellis-coded modulations allow data rates of 7.2, 9.6, 12 and 14.4 Kbps, while non-Trellis-coded modulations support 4.8 and 9.6 Kbps. The symbol rate for every data signaling rate is approximately 2,400 symbols per second.