Abstract: A self-switched in-band signaling communication apparatus is disclosed which enables the switching of the signaling mode to the data mode on a single transmission line between a data terminal equipment or data communication equipment and the data port of a satellite communications controller, and the opposite switching from the data mode to the signaling mode under a single control bit. Signaling to and from the data port of the satellite communications controller is carried out using conventional dialing pulses at a signaling rate which is independent of the line data rate. The apparatus provides for the multipoint communication between a plurality of data terminal equipments using a unique multipoint turn-around process which provides a mobile bandwidth capability for the communications system.

Abstract: Digital exchange stations linked by earth satellite operate in a coordinately controllable time division switching and communication network system relative to externally attached telephone and data trunks. Modular switching equipment operating in coordination with satellite frames establishes and releases connection paths to trunk stores which interface with time and space domain channels of the system. Circuits through the system utilizing these paths are termed virtual connections because in different frames a circuit may be completed through different channels or even blocked under certain conditions. Telephone speech is converted between analog and digital forms relative to modular groups of 96 ports. Digital switching (slot interchange) equipment serving up to four groups (and cycling in coordination with satellite time division frames) cyclically completes local (intra-station) connections between ports and segments of toll (inter-station) connections between ports and locations in the trunk stores.

Abstract: Modular digital exchanges linked by earth satellite provide coordinated time division switching and time compressed communication services relative to externally attached telephone and data (user) trunks. Branch exchange modules (NCU's) perform call switching, buffer storage, time compression and activity selective channel assignment handling between individual external user trunks and multi-bit channels of external time division highways (digital links). The latter are linked pyramidally to time division multiple access nodes of the satellite through Network (Nodal) Access Unit modules (NAU's) which perform further time compression handling and adaptive assignment of satellite channels based upon nodal distribution of demand. The NCU modules also provide "local" switching between user trunks and "tandem" linkage directly between NCU's (without NAU and satellite handling).

Abstract: Digital exchange terminals are linked by earth satellite and terrestrial point-to-point time division trunks in a privately coordinatable time division switching and communication network serving to connectively link multiple ports attachable to separate voice telephone and data communication "subscriber" trunk lines. The terminals operate relative to the satellite in a time division multiple access (TDMA) system with a portion of the system capacity (traffic burst channels) variably allocated to the terminals by demand assignment. The demand assignment is autonomously controlled by the terminals through supervisory communications carried over dedicated satellite channels (Order Wires) also utilized for synchronization. Internally the terminals employ modular multiplex switching between ports and "virtual" channels (buffer stores) and voice activity compression (mapping of groups of up to n virtual channels into groups of up to m, m less than n, actual time division channels on the time division trunks).