Circuit arrangement for telecommunication exchange systems, particularly

Abstract

A telecommunication exchange system has a plurality of switch facilities over which signals are emitted on an average only during a part of their respective occupation. A signal current source for emission of the signals is provided having a call-handling capability limited by signal current load. A signalling system is provided for serving a distribution of the load and provides pulse sequences having respectively identical pulse spacings. Pulses of different pulse sequences simultaneously transmitted over different switch facilities have chronologically different phase relations and a chronological offset from switch facility to switch facility. The offset is such that the pulses of the different pulse sequences connect chronologically to one another with respect to pulse termination and pulse beginning. The switch facilities are allocated for receiving the pulse sequences from the signalling system to a respective one of the pulse sequences of a specific phase relation. The allocation is executable upon consideration of allocations already existing and affecting signalling events. No more than a given number of switch facilities is allocated with respect to the pulse sequences having a respective specific phase relationship. This given number is determined by the signalling current loadability of the current source. With a given allocation of this given number of switch facilities to each of the plurality of phase relations, one or more additional switch facilities request an allocation to a phase relation for signalling, they either receive a signal to abort a setup of the calls or are only allocated a respective phase relation after a given limited delay time if the switch facilities allocated to the phase relation have become fewer than said given number, or if all allocations remain filled at the end of the given delay time, receive the signal to abort setup of the call.