Repeater station for use in a radio relay system to protect time deviations of time slots

Claim 1

A repeater station for repeating a first sequence of downward time slots from a first station to a second station as a second sequence of downward time slots and for transmitting a first succession of upward time slots to said first station in response to a second succession of upward time slots received from said second station, a particular downward time slot in each of said first and said second sequences comprising a synchronizing signal, a particular upward time slot in each of said first and said second successions corresponding to said particular downward time slot, each of said downward and said upward time slots having a predetermined length except for said particular downward and upward time slots, said repeater station including detecting means for detecting the synchronizing signal included in said first sequence to produce a detection signal, wherein the improvement comprises: timing signal producing means responsive to said detection signal for producing a first and a second timing signal when a first predetermined duration lapses after detection of the synchronizing signal included in said first sequence and when a second predetermined duration lapses after production of said first timing signal, respectively; memory means coupled to said timing signal producing information carried in/ means for memorizing\the upward time slots of said second succession; and (Claim 1 continued) reading means responsive to said second timing signal information for reading the upward time slot memorized in said memory means to produce the upward time slots of said first succession.