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品 牌：德國羅德與施瓦茨 | R&S | Rohde&Schwarz

Rohde & Schwarz ESVD EMI Test Receiver, 20 MHz - 1 GHz (2 GHz)

The R&S ESVD Test Receiver is equally suitable for the measurement of signal strength and interference.

For planning and operation of radio networks it is important to know the propagation conditions in the area to be covered. The ESVD Test Receiver features optimal bandwidths for radio services as well as a high measurement rate so that it is ideal for fixed and coverage measurements.

The number of measurements required to ensure electromagnetic compatibility is continuously increasing in the field of RFI measurements. Thanks to the built-in inligence of Test Receiver ESVD, the time required for such measurements is reduced considerably. Being also a specialist for EMI measurements to CISPR, CENELEC, ETSI, FCC, VCCI and VDE standards, the ESVD can furnish results more rapidly and accuray than has been possible up to now.

The R&S ESVD Test Receiver for digital radio networks is a triple-conversion heterodyne receiver covering the frequency range from 20 to 1000 MHz (2050 MHz optionally). Its main features and facilities are:

* RF attenuator switchable in 10-dB steps in the range 0 to 120 dB
* One preselector with fixed tuning and five tracking preselectors, option ESVD-B2 with four additional filters with fixed tuning
* Preamplifier with wide dynamic range, can be switched between preselector and 1st mixer
* Crystal-stabilized synthesizer as 1st LO, variable in 100-Hz steps, sweep mode for fast frequency scans; frequency accuracy complying with GSM recommendations
* High-level mixer ensuring high isolation of 1st LO for converting the input frequency to the first IF (1354.7 MHz or 394.7 MHz)
* High-level mixers for conversion to the second (74.7 MHz) and third (10.7 MHz) IF
* IF filters (10 kHz, 120 kHz, 300 kHz and 1 MHz) in the third IF stage with group-delay optimization
* Precise I/Q demodulator
* Highly linear envelope detector with more than 70 dB dynamic range
* Peak, average and quasi-peak detectors operating in parallel, which enables simultaneous measurements in different weighting modes
* Peak indication with IF bandwidth correction factors for measuring broadband interference (PK/MHz) automatically taken into account
* Measurement monitoring by means of automatic overload detection in the relevant ESVD stages and by the permanently activated peak detector
* Logarithmic amplifier with more than 70 dB dynamic range
* 12-bit A/D converter with short conversion time
* Measurement time selectable between 1 ms and 100 s
* Flash EPROMs allowing convenient and fast firmware updating with the aid of a PC
* Digital level indication on LC display and analog level indication on moving-coil meter taking into account transducer factors and their units
* Automatic calibration at a key-stroke with the aid of a high-precision built-in generator
* Demodulator circuits for FM, AM and A0; built-in loudspeaker and headphones connector
* Automatic monitoring of all synthesizer loops and supply voltages during operation
* Detection of faulty modules by built-in selftest facilities

Design
The service-friendly modular design of ESVD ensures excellent results regarding RFI emission and immunity. A quiet, temperature-controlled blower minimizes self-heating of ESVD. Comprehensive built-in test functions allow any module requiring servicing to be easily identified and replaced independently of other modules.

Functions
ESVD combines three classes of instruments in one:

* the system-compatible test receiver for GSM field-strength and EMI measurements
* the compact, manually tunable and battery-operated test receiver
* the automatic test receiver which performs EMI measurements and reports the results is equally suitable for the measurement of signal strength and interference.

For planning and operation of radio networks it is essential to know the propagation conditions in the area to be covered. Test Receiver ESVD features optimal bandwidths for radio services as well as a high measurement rate so that it is ideal for fixed and coverage measurements.

The number of measurements required to ensure electromagnetic compatibility is continuously increasing in the field of RFI measurements. Thanks to the built-in inligence of Test Receiver ESVD, the time required for such measurements is reduced considerably. Being also a specialist for EMI measurements to CISPR, CENELEC, ETSI, FCC, VCCI and VDE standards, the &S ESVD can furnish results very rapidly and accuray.

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