Double sync burst TDMA system
First Claim
1. Synchronization apparatus for a TDMA communication system for maintaining synchronization regardless of failure of a synchronizing burst transmitted by the reference station, said TDMA communication system having a number of stations communicating with each other in a TDMA mode through a communication link, said synchronization apparatus comprising,means for periodically transmitting a primary synchronization burst,means for periodically transmitting a secondary synchronization burst in at least each frame including a primary synchronizing burst,detecting means at a plurality of said stations for detecting both said synchronization bursts,a burst synchronizer at each of said plurality of stations for maintaining transmission bursts of said station within a pre-assigned time slot, andmeans at said plurality of stations responsive to said detecting means for controlling said burst synchronizer to maintain synchronization even in the absence of said primary synchronization burst.
3 Assignments
0 Petitions
Accused Products
Abstract
A TDMA system in which each station times its respective data burst from a reference sync burst transmitted by a designated primary reference station over the satellite link. Another station transmits a secondary sync burst timed from the primary stations sync burst. To maintain synchronism at the satellite each station has a burst synchronizer operated by receipt of the primary reference sync burst. The secondary sync burst is also received by each of the stations and is capable of ensuring synchronization in case of failure of the primary stations'"'"'s sync burst.
41 Citations
26 Claims
-
1. Synchronization apparatus for a TDMA communication system for maintaining synchronization regardless of failure of a synchronizing burst transmitted by the reference station, said TDMA communication system having a number of stations communicating with each other in a TDMA mode through a communication link, said synchronization apparatus comprising,
means for periodically transmitting a primary synchronization burst, means for periodically transmitting a secondary synchronization burst in at least each frame including a primary synchronizing burst, detecting means at a plurality of said stations for detecting both said synchronization bursts, a burst synchronizer at each of said plurality of stations for maintaining transmission bursts of said station within a pre-assigned time slot, and means at said plurality of stations responsive to said detecting means for controlling said burst synchronizer to maintain synchronization even in the absence of said primary synchronization burst.
-
12. A method of synchronizing a number of stations in a TDMA system for maintaining synchronization in the absence of a primary syncronization burst, said stations communicating with each other through a communication link and in which the communication cycle comprises a repetitive frame including a primary synchronizing burst, the improvement comprising steps of:
-
a. transmitting, for reception by said stations a secondary synchronization burst within said frame, b. synchronizing, at each of said stations to said primary synchronization burst, and c. synchronizing with said secondary synchronization burst in the absence of said primary synchronization burst. - View Dependent Claims (13, 14, 15, 16)
-
-
17. Synchronization apparatus for a TDMA communication system including a plurality of stations for maintaining synchronization regardless of the failure of the synchronizing burst transmitted by the reference station including:
-
means at one of said stations for periodically transmitting a secondary synchronization burst in at least each frame including the reference station synchronizing burst, detecting means at at least one of said stations for detecting both said synchronization bursts, a burst synchronizer at at least said one station for maintaining transmission bursts of said one station within a preassigned time slot, and means at at least one said station responsive to said detecting means for controlling said burst synchronizer to maintain synchronization even in the absence of said reference station'"'"'s synchronization burst. - View Dependent Claims (18, 19, 20, 21, 22, 23, 24, 25, 26)
-
Specification