| 摘要 |
In a cellular data transmission system non-interfering digital communication channels are added to existing analog or digital voice communications channels in the system by utilising frequency space between channels made possible by the co-channel and adjacent channel frequency co-ordination procedures. Interference is prevented by reduction of power, selection of frequencies, proper modulation and demodulation techniques, and unique allocation to the channels in frequency and location. The system is also applicable in general to the insertion of narrow frequency bandwidth channels in any existing communications system using co-channel and adjacent channel frequency allocation strategies. |
