Patent ID: 11949476
Assignee: AJAX SYSTEMS CYPRUS HOLDINGS LTD
Field: Telecommunications (Electrical engineering)
Classification: CPC H | IPC H

Claim 0:
1. A method for a radio communication among a plurality of transceivers (1) and (2) of a safety or control system, the method comprising: broadcasting a radio signal, which comprises at least a preamble and a packet body, and searching for the preamble through a plurality of antennas k1 (5) of one transceiver (2) with an alternate periodical linking of each antenna (5) to search for the preamble; evaluating a quality of the radio signal as compared to a given level of the radio signal upon receipt of the preamble; and selecting an antenna (5) having a maximum level of the radio signal, through which a synchronization of the transceivers (1) and (2) is started to receive the packet body, characterized in that during the broadcasting of the radio signal, a radio frequency is periodically switched among a set of given radio frequencies k2, while during the alternate periodical linking of each antenna (5) to search for the preamble, the radio frequency is periodically switched among the radio frequencies from the set of given radio frequencies k2 for the linked antenna (5), wherein a minimum duration of the preamble for the broadcasting of the radio signal is determined by a ratio T1=(k1+k2) T, where T1 is a duration of the preamble broadcasting in msec, T is a duration of linking of one antenna (5) of the transceiver (2) at a single radio frequency in msec, wherein upon receipt of the preamble during selecting of the antenna (5) having the maximum level of the radio signal, a frequency, at which the preamble has been received, is assigned as a reference (carrier) frequency followed by synchronization of the transceivers (1) and (2) through the selected antenna (5) and the reference frequency.