half-duplex


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Related to half-duplex: Full-duplex

half-duplex

(communications)
(hdx, from telegraphy) 1. A type of communication channel using a single circuit which can carry data in either direction but not both directions at once.

Compare: simplex, full-duplex.

2. An obsolete term for local echo.

half-duplex

The transmission of data in both directions, but only one direction at a time. For example, two-way radio (push-to-talk phones) use half-duplex communications. When one party speaks, the other party listens. Contrast with full-duplex.

Are Cellphones Half-Duplex?
No, but they often sound as if they are. The cellular system generally uses separate transmit and receive channels for a two-way conversation. However, the GSM system switches back and forth between transmit and receive, and it often does not sound like a two-channel, full-duplex system. No digital cellular system is quite like the good old analog days when each phone call had two dedicated channels the entire session. See push-to-talk and GSM.
References in periodicals archive ?
By contrast, the customers that arrived at the SQ will have to wait relatively long due to the half-duplex constraint.
On the other hand, we compare our proposed full-duplex scenarios with the conventional half-duplex scheme in order to show the performance improvement.
Complete broadcast refers to the protocol where the source node is sending a broadcast packet on each available channel one by one; other nodes receive this broadcast packet and forward it on its all available channels one by one, and nodes are in half-duplex communication.
In its free version, PalTalk offers instant messaging, conferences, and chat rooms and is capable of multiparty half-duplex audio and still-frame video with up to three other users.
Secrecy Outage Probability for the System with Half-Duplex DnF Relays
Relay systems are categorized into two types according to the duplex mode: one is the half-duplex relay (HDR) system where the relay receives and retransmits on orthogonal channels (in general, different time slots), while the other is the full-duplex relay (FDR) system where the relay receives and retransmits concurrently [2][3].
One of the simplest relay protocols is the use of a half-duplex two-hop relaying which assists the communication between a base station (BS) and a mobile station (MS) that is geographically located far apart from the BS [2].
However, traditional transmission scenarios are always with one-way relay which is mostly assumed to be half-duplex (HD) mode, resulting in an inherent spectral efficiency loss and poor utilization of resources [6].
VHF (138MHz-225MHz), UHF (406MHz 512MHz) and 869MHz (863MHz--870Mttz) versions of the AutoLog WSN are available for simplex or half-duplex operation.
* The ability to support full-duplex and half-duplex operation, high-speed non-blocking, store-and forward switching and auto-negotiation as well as Layer-2 switching.
It supports a range of half-duplex video applications, including 'see-what-I-see' video sharing on any Series 60 Nokia device.
The software automatically negotiates the Ethernet speed (10Base-T or 100Base-T), as well as choosing between full- and half-duplex operations.