Icom Incorporated

Yoshiyuki Tanaka

Shoji Fukuzawa

Tatsuya Oka

Upon reception of ACK via a communication IF, an allocator allocates a channel of a repeater to be controlled to communications between wireless terminals. A determination unit determines whether channels allocatable to the communications between the wireless terminals are short. When the determination unit has determined that the allocatable channels are short, a switching controller controls at least one repeater, among repeaters to be controlled by a repeater controller, that serves as a controlling repeater to cause the repeater to transmit, to a wireless terminal standing by in the channel of the repeater, a switching signal designating standby in a channel of a repeater that is controlled by another repeater controller.

Multisite trunking system and site switching method

A wireless communication system comprises a relay system including a plurality of relay devices and a plurality of wireless terminal devices. Each relay device transmits control information to the wireless terminal device which is registered in the own relay device, and each wireless terminal device selects, based on the control information received from the relay device which registers the own wireless terminal device, a channel which is currently able to relay a communication among channels respectively allocated to the relay devices to establish a communication between the wireless terminal devices. Each relay device acquires information configuring the control information via a communication line and causes a downlink signal wirelessly transmitted by the own relay device to synchronize with a communication signal, and each wireless terminal device maintains, when shifting a channel for communication to another channel, a synchronized state established in a channel prior to shifting.

Wireless communication system, relay system, repeater devices and synchronization method

When no synchronization signal is transmitted over a system bus (), a master repeater is arbitrarily selected from a plurality of repeaters (to), starts transmitting a synchronization signal over the system bus (), and transmits information to the system bus () in synchronization with the synchronization signal. Other slave repeaters transmit information to the system bus () in synchronization with the synchronization signal transmitted by the master repeater.

Relay system, relay device and synchronization method

Plural repeaters (to) are connected one another via a system bus (), and each of which detects the state of another repeater by checking a signal transmitted over the system bus (). When stopping the operation of home repeater (e.g., the repeater ()) which performs relaying process among wireless terminal devices (TA) to (TH), a secondary repeater (e.g., the repeater ()) set beforehand detects that the home repeater breaks down as the secondary repeater becomes unable to detect the signal over the system bus (). The secondary repeater responds to the detection and bears the relaying process instead of the home repeater.

Wireless communication system, wireless communication method thereof, repeater devices and wireless terminal devices

Wireless terminal devices (TA) to (TH) each detects whether channel information received from each of repeaters () to () indicates an occupied state or an idle state, and when detecting a channel in an idle state, writes identification information of that channel in a RAM (). The wireless terminal devices (TA) to (TH) each selects a piece of identification information of a channel among plural pieces of identification information of a channel written in the RAM () to start making a call to a channel of the selected identification information.

Wireless communication system, wireless communication method, wireless communication terminal device, relay device, and relay system

A wireless terminal device (TA) receives a downlink signal that is repeatedly transmitted from a pre registered home repeater when requesting communication, specifies an idle channel based on idle channel information that is included in the downlink signal, and using the frequency of the uplink signal of the idle channel requests communication permission from the relay device that provides the idle channel. When communication permission cannot be received from the relay device from which communication permission was previously requested, the wireless terminal device (TA) uses the same frequency as the frequency of the downlink signal from the home repeater to transmit a signal to the wireless terminal device (TB) of an intended other party requesting communication.

Wireless terminal device, wireless communication method, and wireless communication system and program

A frequency band of 12.5 kHz that two repeaters (A), (B) are allowed to utilize is divided into two frequency bands, divisional frequency bands of 6.25 kHz are allocated to respective repeaters (A), (B), the repeater (A) which is one specific repeater suspends transmission of a signal at a certain time set beforehand, another repeater (B) is instructed to suspend transmission of a signal, and after signal transmission at individual repeaters (A), (B) are suspended, the repeater (A) transmits a defined CW-ID signal which is a call signal given to the whole two repeaters (A), (B).

Relay device, wireless communication method, and wireless communication system

There is provided a wireless communication system which causes a wireless terminal to select a relay device among plural relay devices connected together via a communication line when the wireless terminal attempts to communicate with another wireless terminal. The relay device has an information acquiring unit, a calling determining unit, and an information adding unit. The wireless terminal has an information analyzing unit which analyzes whether or not the own device is included in a communication counterparty of calling information when the calling information is included in communication information, a priority comparing unit which determines whether or not a priority level of the calling information is higher than that of a current communication when the own device is included, and a channel changing unit which changes a channel to that of another relay device of the calling information when the priority level of the calling information is higher.

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Osaka, Japan

Yoshiyuki Tanaka