Abstract: A technique for providing volume adjustment capabilities in a digital telecommunication system. A composite two-part address is applied to a memory which stores amplitude adjusted digital voice words. The first part of the address comprises the digital voice word carried by the TDM time slot. The second part of the address comprises a parameter which defines the extent of amplitude adjustment. The readout of the memory thereby defines a different digital voice word having a desired amplitude level. The second address part of the composite address is generated by an amplitude parameter memory in synchronism with each time slot so that the amplitude of the digital voice words in corresponding time slots can be adjusted independently and dynamically with respect to the others.

Abstract: A communication system having full call processing capabilities in the user ports, each port being connected to a TDM collection bus and a TDM distribution bus. A bus controller terminates the collection bus on which voice words are deposited in time slots by the respective user ports, the voice words being realigned and transmitted by the bus controller on the TDM distribution bus. Each user port is assigned a time slot and can thus communicated simultaneously with one or more other user ports, such as during a two-way telephone conversation or a multiple party conference call. A memory in each user port combines plural voice words obtained from respective TDM time slots of conference participants, and combines such voice words into a composite signal representative of all the other conferees. The conference circuit of each user port combines the voice words of all the other participating ports over a frame period, except its own voice word, and thus the composite voice word of each user port is different.