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It simply means how many transponders would be used if the same total bandwidths used only 36 MHz transponders. [3] [4] [5] So, for example, the ARSAT-1 has 24 IEEE K u band transponders: 12 with a bandwidth of 36 MHz, 8 with 54 MHz, and 4 with 72 MHz, which totals to 1152 MHz, or 32 TPE (i.e., 1152 MHz divided by 36 MHz). [6] [7]
A Highway 407 toll transponder. In telecommunications, a transponder is a device that, upon receiving a signal, emits a different signal in response. [1] The term is a blend of transmitter and responder. [2] [3]
The transponder emits a signal when it is interrogated by the secondary radar. In a transponder based system signals drop off as the inverse square of the distance to the target, instead of the fourth power in primary radars. As a result, effective range is greatly increased for a given power level.
A transponder (short for transmitter-responder [1] and sometimes abbreviated to XPDR, [2] XPNDR, [3] TPDR [4] or TP [5]) is an electronic device that produces a response when it receives a radio-frequency interrogation.
Soon after the introduction of radar, the radio transponder appeared. Transponders are a combination of receiver and transmitter whose operation is automated – upon reception of a particular signal, normally a pulse on a particular frequency, the transponder sends out a pulse in response, typically delayed by some very short time.
The footprint of a communications satellite is the ground area that its transponders offer coverage, and determines the satellite dish diameter required to receive each transponder's signal. There is usually a different map for each transponder (or group of transponders), as each may be aimed to cover different areas.
Frequency-hopping spread spectrum (FHSS) is a method of transmitting radio signals by rapidly changing the carrier frequency among many frequencies occupying a large spectral band. The changes are controlled by a code known to both transmitter and receiver .
As traffic density goes up, the system's range goes down, and the frequency of updates becomes more random. For this reason VHF Data Exchange System (VDES) has been developed: [ 18 ] it will operate on additional new frequencies and will use them more efficiently, enabling thirty-two times as much bandwidth for secure communications and e ...