| 摘要 |
<P>PROBLEM TO BE SOLVED: To secure a communication passage with excellent communication quality without disconnecting data communication. <P>SOLUTION: Communication equipment includes: an observing part 30 for observing a data transmitting/receiving states in a main data transmitting/ receiving part 10 for transmitting data which are modulated by a first modulating/demodulating part 11 or a second modulating/demodulating part 12 by a main frequency channel, and a sub-data transmitting/receiving part 20 for transmitting data which are modulated by a third modulating/ demodulating part 21 or a fourth modulating/demodulating part 22 by a sub- frequency channel that is a frequency channel being different from the main frequency channel; a comparing part 40 for comparing the observation results; main frequency channel change-over parts 16 and 40 for changing-over the main frequency channel based on the comparison result; and modulation type change-over parts 30 and 40 for performing change-over into one of the first modulating/demodulating part for modulation by a first modulation system and the second modulating/demodulating part for modulation by a second modulation system based on the comparison result. <P>COPYRIGHT: (C)2003,JPO |
