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EP0473355A2
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Distributed multisite coordination system for trunked radio systems
Assignee: Ericsson Inc
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Filing: 1991-08-21
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Granted: —
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Expires: 2011-08-21
Abstract
Abstract A multisite network switch for a series of RF digital trunked radio transceivers and dispatcher consoles. Each transceiver covers a certain site area. The switch establishes audio communications between different sites and various dispatcher consoles. The multisite switch has a distributed architecture in which each node of the switch is supported by a microprocessor controlled card. Each node interfaces with a site, dispatcher console, system manager or other system component.
Inventors
- 👤 James L. Teel
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-29 21:09
CPC Classifications
H; H04; H04W; H04W84/00; H04W84/02; H04W84/04; H04W84/08; H04W4/00; H04W4/06; H04W4/10; H04W76/00; H04W76/40; H04W76/45
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
81 words
A local area network for a radio frequency multicasting system including a multisite switch comprising: a first microprocessor controlled node coupled through a first data link and to a first trunked audio link to said first transmitter; a second microprocesser controlled node coupled through a second data link and to a second trunked audio link to said second transmitter; an audio bus including a plurality of slots conveying audio communications between said transmitters, said nodes controlling slot assignments for said communications.
Claim 2
Dependent Claim
18 words
A local area network as in claim 1 wherein said first and second nodes are MIMs and CIMs.
Claim 3
Dependent Claim
34 words
A local area network as in claim 1 wherein said first and second nodes have a dynamic addressing means for assigning unique addresses to said nodes by each node selecting its own unique address.
Claim 4
Dependent Claim
51 words
A local area network as in claim 1 further comprising a message bus operatively coupled to said first and second nodes whereby said nodes maintain a bus/slot bit map representative of the status of each audio bus and slot and a redundant message discard means for discarding redundant slot status messages.
Claim 5
Dependent Claim
25 words
A local area network as in any of claims 1 to 4 wherein the microprocessor controlled nodes include databases for units, groups and group counts.
Claim 6
Dependent Claim
185 words
In a radio frequency multicasting system of the type having a central switch controlled by a local area network of nodes each having one or more microprocessor supported audio cards connected to a slotted audio bus within the switch, a controller card coupled to said audio cards and to a message bus within said switch, and plurality of radio frequency site controllers each coupled to an individual switch node, a method of establishing audio communications between said transmitters and through said switch comprising the steps of: receiving a channel assignment at a first node of the switch from a first site controller; generating an audio slot assignment message in said first node and placing the slot assignment message on the message bus; upon receipt of the slot assignment message from the bus, a second node sending a channel request to a second site controller operatively coupled to said second node; sending a second channel assignment to the second node from the second site controller; sending audio signals from the first site controller to the second site controller over the assigned audio slot on the switch.
References Cited (Backward Citations)
No citation records indexed.
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