| 摘要 |
<p>An inbuilding communication system is described for providing telephone communication between sets of portable telephone (58) located in different areas (13-15, 17-19) of a building (12 or 16), wherein each set of portable telephones is assigned a substantially identical set of frequencies. The various areas (13-15, 17-19) are separated by building structure which attenuates radio signals. Each area is provided with a set of at least two antennas (54-56, 64-66, 74-76, 94-96, 104, 106, 108, 114, 116, 118) the number and position of each antenna being chosen such that the radio signals transmitted from such antennas are attenuated below a predetermined level from passing through the attenuating structure. A selection circuit (52) is provided for selecting one antenna in each set for transmitting a selected radio signal, such antenna being selected to that which requires the lowest signal intensity for transmitting to the portable telephone in that area corresponding to a particular frequency.</p> |
