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Duplex (telecommunications)
A duplex communication system is a point-to-point system composed of two or more connected parties or devices that can communicate with one another in both directions. Duplex systems are employed in many communications networks, either to allow for simultaneous communication in both directions between two connected parties or to provide a reverse path for the monitoring and remote adjustment of equipment in the field. There are two types of duplex communication systems: full-duplex (FDX) and half-duplex (HDX). In a full-duplex system, both parties can communicate with each other simultaneously. An example of a full-duplex device is plain old telephone service; the parties at both ends of a call can speak and be heard by the other party simultaneously. The earphone reproduces the speech of the remote party as the microphone transmits the speech of the local party. There is a two-way communication channel between them, or more strictly speaking, there are two communication channel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Voice Operated Switch
In telecommunications, a voice operated switch, also known as VOX or voice-operated exchange, is a switch that operates when sound over a certain threshold is detected. It is usually used to turn on a transmitter or recorder when someone speaks and turn it off when they stop speaking. It is used instead of a push-to-talk button on transmitters or to save storage space on recording devices. On cell phones, it is used to save battery life. Intercom systems that use a speaker in a room as both a speaker and a microphone will often use VOX on the main console to switch the audio direction during a conversation. The circuit usually includes a delay between the sound stopping and switching direction, to avoid the circuit turning off during short pauses in speech. A special case exists, if there is enough energy to power the system directly. For example, a microphone may send a voltage high enough to directly operate a transmitter. Comparison with push-to-talk Unlike manual push-to-ta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mobile App
A mobile application or app is a computer program or software application designed to run on a mobile device such as a smartphone, phone, tablet computer, tablet, or smartwatch, watch. Mobile applications often stand in contrast to desktop applications which are designed to run on desktop computers, and web applications which run in mobile web browsers rather than directly on the mobile device. Apps were originally intended for productivity assistance such as email, calendar, and contact databases, but the public demand for apps caused rapid expansion into other areas such as mobile games, factory automation, GPS and location-based services, order-tracking, and ticket purchases, so that there are now millions of apps available. Many apps require Internet access. Apps are generally downloaded from app stores, which are a type of digital distribution platforms. The term "app", short for "Application software, application", has since become very popular; in 2010, it was listed as " ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hytera
Hytera (; previously HYT; ) is a Chinese publicly traded and partly state-owned manufacturer of radio transceivers and radio systems founded in Shenzhen, Guangdong in 1993. Hytera is listed on the Shenzhen Stock Exchange and is partly owned by Shenzhen Investment Holdings of Shenzhen's municipal government. Hytera is major contributor to the PDT Standard, which is designed for public safety organizations in China. The company is a major supplier to China's Ministry of Public Security. History The company's head office is in Shenzhen, China. Hytera's products are developed at three development sites in total. One of the development sites is located in Bad Münder, Germany. In March 2012 Hytera acquired the German company Rohde & Schwarz Professional Mobile Radio GmbH from the German electronics group Rohde & Schwarz, which is now known as Hytera Mobilfunk. In addition, there are Hytera subsidiaries in the US, UK, Canada, and Spain. United States In June 2007, Hytera acquire ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Half-duplex
A duplex communication system is a point-to-point system composed of two or more connected parties or devices that can communicate with one another in both directions. Duplex systems are employed in many communications networks, either to allow for simultaneous communication in both directions between two connected parties or to provide a reverse path for the monitoring and remote adjustment of equipment in the field. There are two types of duplex communication systems: full-duplex (FDX) and half-duplex (HDX). In a full-duplex system, both parties can communicate with each other simultaneously. An example of a full-duplex device is plain old telephone service; the parties at both ends of a call can speak and be heard by the other party simultaneously. The earphone reproduces the speech of the remote party as the microphone transmits the speech of the local party. There is a two-way communication channel between them, or more strictly speaking, there are two communication channel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Telephone Call
A telephone call, phone call, voice call, or simply a call, is the effective use of a connection over a telephone network between the calling party and the called party. Telephone calls are the form of human communication that was first enabled by the development of the telephone and several inventions in the mid- to late-19th century. Initial technology involved point-to-point electrical wire connections between telephone installations, until centralized exchanges evolved where Switchboard operator, telephone operators established each interconnection manually at a telephone switchboard after asking the calling party for their call destination. After the invention of automatic telephone exchanges in the 1890s, the process became increasingly automated, eventually leading to the widespread adoption of digital exchanges in the second half of the 20th century, including the transition to wireless communication via mobile telephone networks and cellular networks. With the developm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cellular Phone
A mobile phone or cell phone is a portable telephone that allows users to make and receive calls over a radio frequency link while moving within a designated telephone service area, unlike fixed-location phones ( landline phones). This radio frequency link connects to the switching systems of a mobile phone operator, providing access to the public switched telephone network (PSTN). Modern mobile telephony relies on a cellular network architecture, which is why mobile phones are often referred to as 'cell phones' in North America. Beyond traditional voice communication, digital mobile phones have evolved to support a wide range of additional services. These include text messaging, multimedia messaging, email, and internet access (via LTE, 5G NR or Wi-Fi), as well as short-range wireless technologies like Bluetooth, infrared, and ultra-wideband (UWB). Mobile phones also support a variety of multimedia capabilities, such as digital photography, video recording, and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PoC Radio
A PoC radio (short for push to talk over cellular radioLakisha Davis. ), also known as PTToC radio, is an instant communication device that is based on the cellular network. It is a radio device that incorporates push-to-talk technology into a cellular radio handset. It allows users to communicate with one or more receivers instantly, in a half-duplex mode. Although a PoC radio is a walkie-talkie-like device, there are substantial differences between them. Compared to the latter, the former has a wider range of channels, covers a wider area, and does not require a license to transmit. In addition, a PoC radio supports advanced functions, such as, video calls, multimedia messages, GPS location tracking, and emergency notifications. PoC radios are widely used in the industries of private security, logistics, hospitality, and rescue. The representative manufacturers of such equipments include Hytera and ToooAir. Mission-Critical PTToC (MCPTT) is also starting to be employed i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PTT ID
PTT ID, or Push-To-Talk ID, is a generic term for an automatic number identification (ANI)-like system used in two-way radio systems. It provides identification of the transmitting radio over the air, and is commonly used in selective calling In a conventional, analog two-way radio system, a standard radio has ''noise squelch'' or ''carrier squelch'', which allows a radio to receive all transmissions. Selective calling is used to address a subset of all two-way radios on a single ra .../signaling systems, usually in commercial and public safety radio systems. PTT ID features are included in MDC-1200 and other signaling systems. Radio technology {{radio-comm-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Citizens Band
Citizens band radio (CB radio) is a land mobile radio system, a system allowing short-distance one-to-many bidirectional voice communication among individuals, using two-way radios operating near 27 MHz (or the 11-m wavelength) in the high frequency or shortwave band. Citizens band is distinct from other personal radio service allocations such as FRS, GMRS, MURS, UHF CB and the Amateur Radio Service ( "ham" radio). In many countries, CB operation does not require a license and may be used for business or personal communications. Like many other land mobile radio services, multiple radios in a local area share a single frequency channel, but only one can transmit at a time. The radio is normally in receive mode to receive transmissions of other radios on the channel; when users want to communicate they press a " push to talk" button on their radio, which turns on their transmitter. Users on a channel must take turns transmitting. In the US and Canada, and in the EU an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Two-way Radio
A two-way radio is a radio transceiver (a radio that can both transmit and receive radio waves), which is used for bidirectional person-to-person voice communication with other users with similar radios, in contrast to a broadcast receiver, which only receives transmissions. Two-way radios usually use a half-duplex communication channel, which permits two-way communication, albeit with the limitation that only one user can transmit at a time. (This is in contrast to simplex communication, in which transmission can only be sent in one direction, and full-duplex, which allows transmission in both directions simultaneously.) This requires users in a group to take turns talking. The radio is normally in receive mode so the user can hear all other transmissions on the channel. When the user wants to talk, they press a " push-to-talk" button, which turns off the receiver and turns on the transmitter; when the button is released, the receiver is activated again. Multiple channels are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
