| 摘要 |
PROBLEM TO BE SOLVED: To provide a communication method, with which 'power line modem to operate in low speed mode', 'power line modem to operate in high speed mode' and 'power line modem of high speed access system' can coexist on the same power line. SOLUTION: In the case of communication between a power line modem 2a capable of performing the communication of a high speed access system and a power line modem 3 to operate in a high speed mode, one modem, which desires the communication, judges time, when data transmission is once circulated by all the power line modem to operate as the slaves of high speed access system communication on the basis of a polling tone and at that time, data communication is performed while using any tone except for default tone and polling tone. In the case of communication between the power line modem 2a and communication equipment 3 to operate in a low speed mode, the communication equipment of one side, which requests the communication, performs data communication while using any tone except for default tone and polling tone in spite of the above time. |
