Measuring receiver

From Wikipedia, the free encyclopedia

This article does not cite any references or sources. (December 2006)
Please help improve this article by adding citations to reliable sources. Unverifiable material may be challenged and removed.

In telecommunication, a measuring receiver or measurement receiver is a calibrated laboratory-grade radio receiver designed to measure the characteristics of radio signals. The parameters of such receivers (tuning frequency, receiving bandwidth, gain) can usually be adjusted over a much wider range of values than is the case with other radio receivers. Their circuitry is optimized for stability and to enable calibration and reproducible results. Some measurement receivers also have especially robust input circuits that can survive brief impulses of more than 1000 V, as they can occur during measurements of radio signals on power lines and other conductors.

1 Applications
2 Types
3 Manufacturers and products
4 See also

[edit] Applications

Measuring receivers are used with calibrated antennas to

determine the signal-strength and standards-compliance of broadcast signals,
investigate and quantify radio-frequency interference,
determine compliance of a device with electromagnetic interference and TEMPEST standards and regulations.

Measuring receivers are also used without antennas to

calibrate RF attenuators and signal generators.

Measuring receivers are widely used in metrology and calibration lab environments, spectrum monitoring and electromagnetic-compatibility facilities.

[edit] Types

Depending on the intended application area, several types of measuring receivers can be distinguished:

Spectrum analyzers are intended to graphically display the amplitude spectrum of a radio signal on a logarithmic scale.

Modulation analyzers are intended to accurately measure not only the signal power level, but also the degree of modulation (such as AM depth, FM/PM deviations), and modulation distortions.

EMC receivers are designed to comply with the detailed equipment requirements of measurement standards for radio interference, such as the civilian specification CISPR 11 or the military specification MIL-STD-461. For example, they include a special quasi-peak detector that has been standardized to estimate the annoyance level of clicks to users of analog radio receivers.

TEMPEST receivers are designed to comply with the requirements of measurement standards for compromising-emanations such as SDIP-27 or NSTISSAM TEMPEST/1-92. For example, their frequency range extends down to acoustic frequencies (typically 100 Hz), their bandwidth can be adjusted in 1-2-5 steps from a few hertz to more than 100 MHz, and their sensitivity and noise figure aims to be close to what is technically feasible.

Some measuring receivers (such as Agilent’s N5531S) also include a signal analyzer, power meter, and a sensor module to allow the instruments to be used together or individually for general-purpose measurement tasks.

[edit] Manufacturers and products

Agilent
Dynamic Sciences
- DSI-450 and DSI-600 EMI test receivers
- R-1250 and R-1550-A TEMPEST test receivers
Electro-Metrics
Rohde & Schwarz
- FSG and FMx series signal and modulation analyzers
- ESU, ESIB, and ESCI measuring receivers for EMC and field-strength measurements
- FSET series TEMPEST preselectors, spectrum analyzers and measuring receivers