METHOD AND DEVICE FOR SEEKING A FREE CHANNEL IN A MOBILE RADIO SYSTEM

摘要

A method and device for seeking a free channel in a mobile radio system. In this method the search for a free channel for communication between a fixed (F) and a mobile (M) station is conducted in the mobile station. The fixed station (F) detects the engaged duplex channels in the rising path and transmits the list of them via the semaphore path. According to the invention, all the fixed stations (Fj), (F) also transmit via the semaphore channels allocated to them the list of channels which they use. In the mobile station the received level of the fixed stations (Fj) in the semaphore path channels is measured and compared with an interference threshold to provide the interfering fixed stations. The mobile station (M) determines the engaged channels in the descending path as being those used by interfering fixed stations. A free channel may then be selected in the mobile station (M) from among those which are engaged neither in the rising nor in the descending path. Application : mobile radio Reference : Figure 4