Tentative reduction of analog cellular facsimile communication time
Hiroki Uchiyama, Harumi Kokaji, Masao Kasuga, Tetsuya Kagawa · Electronics and Communications in Japan (Part I Communications) · 1995
Abstract Various studies have been done, mainly from the viewpoint of improving image deterioration on G3 facsimile transmission using analog cellular channels. This paper discusses communication time with analog cellular facsimile transmission using ITU‐T's error correction mode (ECM). the communication state graph proposed shows its transmission state. Then the protocol of standard ITU‐T's ECM is studied and an effective fall‐back method is proposed. the goal is to use a 9600 bps modem rate, which is not used in analog cellular facsimile transmission, and then an effective fall‐back, e.g., from 9600 bps to 7200 bps, is performed in the case of poor line conditions. This method allows the communication time in analog cellular facsimile transmission to be shortened. Results of field experiments have revealed that a shorter communication time can be achieved with the proposed method than with the conventional transmission method.