| 摘要 |
A new data communication system is described which enables data transmission over existing telephone lines at rates higher than possible with existing methods, including conventional modems. By using a novel asymmetric configuration of the two communication endpoints, the currcntly-accepted maximum theoretical limits on the data rate are no longer applicable. One endpoint is connected directly to a digital telephone network, whereas the other endpoint uses a conventional telephone connection. This reduces the transmission problem to compensation for a single telephone line interface and a single analog local loop. Means of providing this compensation and the required clock synchronization were also created, enabling a practical implementation of the system. The new system can achieve rates up to 64,000 bits-per-second and has broad utility in several active areas including wideband audio transmission, video transmission, networking, facsimile transmission, and remote computer access. |
