摘要 |
To transmit the service signals of a digital radio beam, the carrier is modulated in accordance with a supplementary state in a special modulator when two successive data words are identical. On reception a special demodulator detects the transmission of a service bit having a value 1. The transmission of a service bit having a value 0 takes place by the detection in a comparator of two successive identical data words simultaneously with the detection of the non-transmission of the supplementary state. This supplementary modulation state advantageously corresponds to the elimination of the carrier. |