Form of amateur radio data communications using the AX25 protocol
Terminal Node Controller 2400 baud packet radio modem
In digital radio, packet radio is the application of packet switching techniques to digital radio communications. Packet radio uses a packet switching protocol as opposed to circuit switching or message switching protocols to transmit digital data via a radio communication link.
Packet radio is frequently used by amateur radio operators. The AX.25 (Amateur X.25) protocol was derived from the X.25 data link layer protocol and adapted for amateur radio use. Every AX.25 packet includes the sender's amateur radio callsign, which satisfies the US FCC requirements for amateur radio station identification. AX.25 allows other stations to automatically repeat packets to extend the range of transmissions. It is possible for any packet station to act as a digipeater, linking distant stations with each other through ad hoc networks. This makes packet radio especially useful for emergency communications.
Packet radio can be used in mobile communications. Some mobile packet radio stations transmit their location periodically using the Automatic Packet Reporting System (APRS). If the APRS packet is received by an "igate" station, position reports and other messages can be routed to an internet server, and made accessible on a public web page. This allows amateur radio operators to track the locations of vehicles, hikers, high-altitude balloons, etc., along with telemetry and other messages around the world.
Some packet radio implementations also use dedicated point-to-point links such as TARPN. In cases such as this, new protocols have emerged such as Improved Layer 2 Protocol (IL2P) supporting forward error correction for noisy and weak signal links.
In digital radio, packetradio is the application of packet switching techniques to digital radio communications. Packetradio uses a packet switching...
General PacketRadio Service (GPRS), also called 2.5G, is a packet orientated mobile data standard on the 2G cellular communication network's global system...
The Spartan PacketRadio Experiment (SPRE) was an Amateur Radio communications experiment that flew on the Space Shuttle Endeavour's STS-72 mission as...
Automatic Packet Reporting System (APRS) is an amateur radio-based system for real time digital communications of information of immediate value in the...
The PacketRadio Van was a GMC van refitted by Don Cone at SRI International, and equipped with technology that was used in the first two-way internetworked...
Cigarette packet Sugar packet Network packet, a formatted unit of data carried by a packet-mode computer network Packetradio, a form of amateur radio data...
telecommunications, packet switching is a method of grouping data into packets that are transmitted over a digital network. Packets are made of a header...
retransmits the data packet on another frequency. Packetradio – a long-distance peer-to-peer wireless ad-hoc network in which data packets are exchanged between...
Similar experiments took place in the amateur radio community with the x25 protocol. These early packetradio systems predated the Internet, and indeed were...
Packet loss occurs when one or more packets of data travelling across a computer network fail to reach their destination. Packet loss is either caused...
part of the general packetradio service (GPRS) which allows 2G, 3G and WCDMA mobile networks to transmit Internet Protocol (IP) packets to external networks...
required cumbersome mechanical equipment. Hams led the development of packetradio in the 1970s, which has employed protocols such as AX.25 and TCP/IP....
therefore it can be received by any LAN client. Stations participating in packetradio networks based on the AX.25 link layer protocol also use beacon transmissions...
The Common Public Radio Interface (CPRI) standard defines an interface between Radio Equipment Control (REC) and Radio Equipment (RE). Oftentimes, CPRI...
communications, first by circuit-switched transport, then by packet data transport via General PacketRadio Service (GPRS), and Enhanced Data Rates for GSM Evolution...
of message delivery over a communication channel, such as Ethernet or packetradio, in a communication network. The data that these messages contain may...
provided by the packet data network. APN is used in 3GPP data access networks, e.g. General PacketRadio Service (GPRS) and evolved by packet core (EPC)....
real-time applications like video conferencing. The General PacketRadio Service (GPRS) is a packet-switched data transmission protocol, which was incorporated...
communications protocols used to carry general packetradio service (GPRS) within GSM, UMTS, LTE and 5G NR radio networks. In 3GPP architectures, GTP and Proxy...
GERAN: essentially the same as GRAN but specifying the inclusion of EDGE packetradio services UTRAN: UMTS E-UTRAN: The Long Term Evolution (LTE) high speed...
respect, DTX indirectly improves the over-all capacity of a network. In packetradio systems such as GPRS/EDGE, it is possible to combine DTX with capacity...
air (rather than in fiber optic cable). Packetradio connects computers or whole networks operated by radio amateurs with the option to access the Internet...
5G and 3G mobile phones with the widespread introduction of General PacketRadio Service (GPRS), using a slotted-ALOHA random-access channel combined...
voice (FM, SSB) and data (AX.25, packetradio, APRS) communications. Currently, over 18 fully operational amateur radio satellites are in orbit. They may...
with students. The Service Module IORS radio typically is used for packetradio operations like Automatic Packet Reporting System activities or Slow-scan...
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