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Traffic announcement (TA) refers to the broadcasting of a specific type of traffic report on the Radio Data System. It is generally used by motorists, to assist with route planning, and for the avoidance of traffic congestion.
The RDS-enabled receiver can be set to pay special attention to this TA flag and e.g. stop the tape/pause the CD or retune to receive a Traffic bulletin. The related TP (Traffic Programme) flag is used to allow the user to find only those stations that regularly broadcast traffic bulletins, whereas the TA flag is used to stop the tape or raise the volume during a traffic bulletin.
On some modern units, traffic reports can also be recorded and stored within the unit, both while the unit is switched on, but also for a pre-set period after the unit is turned off. It may also have in-built timers to seek and record the same for two separate daily occasions, e.g., one setting for before the morning commute, and the second for the evening return journey. These messages may then subsequently be recalled on demand by the driver. This specific function is known as TIM, or traffic information message.
Signals intelligence (SIGINT) is the act and field of intelligence-gathering by interception of signals, whether communications between people or from electronic signals not directly used in communication. As classified and sensitive information is usually encrypted, signals intelligence may necessarily involve cryptanalysis. Traffic analysis—the study of who is signaling to whom and in what quantity—is also used to integrate information, and it may complement cryptanalysis.
A teleprinter is an electromechanical device that can be used to send and receive typed messages through various communications channels, in both point-to-point and point-to-multipoint configurations.
An email client, email reader or, more formally, message user agent (MUA) or mail user agent is a computer program used to access and manage a user's email.
Radio Data System (RDS) is a communications protocol standard for embedding small amounts of digital information in conventional FM radio broadcasts. RDS standardizes several types of information transmitted, including time, station identification and program information.
An answering machine, answerphone, or message machine, also known as telephone messaging machine in the UK and some Commonwealth countries, ansaphone or ansafone, or telephone answering device (TAD), is used for answering telephone calls and recording callers' messages.
An Internet forum, or message board, is an online discussion site where people can hold conversations in the form of posted messages. They differ from chat rooms in that messages are often longer than one line of text, and are at least temporarily archived. Also, depending on the access level of a user or the forum set-up, a posted message might need to be approved by a moderator before it becomes publicly visible.
DirectBand was a North American wireless datacast network owned and operated by Microsoft. It used FM radio broadcasts in over 100 cities to constantly transmit data to a variety of devices, including portable GPS devices, wristwatches and home weather stations.
Autofahrer-Rundfunk-Informationssystem was a system for indicating the presence of traffic information in FM broadcasts used by the German ARD network of FM radio stations from 1974. Developed jointly by IRT and Blaupunkt, it indicated the presence of traffic announcements through manipulation of the 57kHz subcarrier of the station's FM signal.
A broadcast flag is a bit field sent in the data stream of a digital television program that indicates whether or not the data stream can be recorded, or if there are any restrictions on recorded content. Possible restrictions include the inability to save an unencrypted digital program to a hard disk or other non-volatile storage, inability to make secondary copies of recorded content, forceful reduction of quality when recording, and inability to skip over commercials.
Traffic analysis is the process of intercepting and examining messages in order to deduce information from patterns in communication. It can be performed even when the messages are encrypted. In general, the greater the number of messages observed, the greater information be inferred. Traffic analysis can be performed in the context of military intelligence, counter-intelligence, or pattern-of-life analysis, and is also a concern in computer security.
The GPRS core network is the central part of the general packet radio service (GPRS) which allows 2G, 3G and WCDMA mobile networks to transmit Internet Protocol (IP) packets to external networks such as the Internet. The GPRS system is an integrated part of the GSM network switching subsystem.
Professional mobile radio are person-to-person two-way radio voice communications systems which use portable, mobile, base station, and dispatch console radios. PMR systems are based on such standards as MPT-1327, TETRA, APCO 25, and DMR which are designed for dedicated use by specific organizations, or standards such as NXDN intended for general commercial use. These systems are used by police, fire, ambulance, and emergency services, and by commercial firms such as taxis and delivery services. Most systems are half-duplex, in which multiple radios share a common radio channel, and only one can transmit at a time. Transceivers are normally in receive mode, the user presses a push-to-talk button on his microphone when he wants to talk, which turns on his transmitter and turns off his receiver. They use channels in the VHF and UHF bands, giving them a limited range, usually 3 to 20 miles depending on terrain. Output power is typically limited to 4 watts. Repeaters installed on tall buildings, hills or mountain peaks are used to increase the range of systems.
Traffic Message Channel (TMC) is a technology for delivering traffic and travel information to motor vehicle drivers. It is digitally coded using the ALERT C or TPEG protocol into Radio Data System (RDS) carried via conventional FM radio broadcasts. It can also be transmitted on Digital Audio Broadcasting or satellite radio. TMC allows silent delivery of dynamic information suitable for reproduction or display in the user's language without interrupting audio broadcast services. Both public and commercial services are operational in many countries. When data is integrated directly into a navigation system, traffic information can be used in the system's route calculation.
Datacasting is the transmission of data over a wide area using radio waves. It typically refers to supplemental information sent by television stations alongside digital terrestrial television (DTT) signals. However, datacasting can also be applied to digital data signals carried on analog TV or radio broadcasts.
The automatic identification system (AIS) is an automatic tracking system that uses transceivers on ships and is used by vessel traffic services (VTS). When satellites are used to receive AIS signatures, the term Satellite-AIS (S-AIS) is used. AIS information supplements marine radar, which continues to be the primary method of collision avoidance for water transport. Although technically and operationally distinct, the ADS-B system is analogous to AIS and performs a similar function for aircraft.
Traffic reporting is the near real-time distribution of information about road conditions such as traffic congestion, detours, and traffic collisions. The reports help drivers anticipate and avoid traffic problems. Traffic reports, especially in cities, may also report on major delays to mass transit that does not necessarily involve roads. In addition to periodic broadcast reports, traffic information can be transmitted to GPS units, smartphones, and personal computers.
An all-points bulletin (APB) is an electronic information broadcast sent from one sender to a group of recipients, to rapidly communicate an important message. The technology used to send this broadcast has varied throughout time, and includes teletype, radio, computerized bulletin board systems (CBBS), and the Internet.
MDC, also known as Stat-Alert, MDC-1200 and MDC-600, is a Motorola two-way radio low-speed data system using audio frequency shift keying, (AFSK). MDC-600 uses a 600 baud data rate. MDC-1200 uses a 1,200 baud data rate. Systems employ either one of the two baud rates. Mark and space tones are 1,200 Hz and 1,800 Hz. The data are sent in bursts over the radio system's voice channel.
Telex is a telecommunication service that provides text-based message exchange over the circuits of the public switched telephone network or by private lines. The technology operates on switched station-to-station basis with teleprinter devices at the receiving and sending locations. Telex was a major method of sending text messages electronically between businesses in the post–World War II period. Its usage went into decline as the fax machine grew in popularity in the 1980s.
GEWI was founded in 1992 by Hagen Geppert and Dr. Karl Will. The “GEWI” name is derived from the first two letters of the two founders’ last names. GEWI began as a specialist developer of programmable hardware for global television manufacturers, with customers such as Sony and Grundig. In 1997, GEWI produced one of the world's first FM receivers to collect RDS-TMC data to display on video monitors at airports.