Precision Calibrated Noise Sources

Features  
Noise Sources Datasheet

Case study:
ISSN-06 in Rohde&Schwarz
signal and spectrum analyzer

  • ENR 12…15 dB typical
  • High stability
  • Good flatness
  • No high voltage supply required
  • Compact solid state source
  • High reliability, rugged construction
Applications
  • Measurement and test equipment
  • Mm-wave noise source
  • Calibration
  • Noise figure measurement
  • Сompatible with noise figure meters for all brand names
Description
     ELVA-1’s calibrated noise source ISSN-XX series delivers a uniform level of noise power spectral density within the whole waveguide frequency range. Sources are available in eight waveguide bands covering 26.4-170 GHz. A Silicon IMPATT diode is employed as a fundamental building block of the source. High stability of the device allows it to be used for test and instrumentation applications in place of gas-tube noise sources. Low DC power requirements eliminate the need for complex high voltage supplies. There are two operation modes: CW mode and pulsed AM mode with modulation frequency up to 1 kHz. Typical value of excess noise ratio (ENR) as a function of frequency is given on the plot below.
Block Diagram of Noise Source
Inputs and Controls:

Notes:

  • Power/Triggering Inversion Switch can be used for manual ON/OFF. “INV” position is ON.
  • Microwave power can be switched with TTL-level control voltage.
  • If Triggering Inversion Switch is in OFF (Down) position active level is high, otherwise (INV position) – active level is low.
  • Each source supplied calibrated relative to liquid nitrogen cooled load. 

Specifications

Model Number ISSN-28 ISSN-22 ISSN-19 ISSN-15 ISSN-12 ISSN-10 ISSN-08 ISSN-06
Frequency Band Ka Q U V E W F D
and Range, GHz 26.5-40 33-50 40-60 50-75 60-90 75-110 90-140 110-170
Input waveguide WR28 WR22 WR19 WR15 WR12 WR10 WR8 WR6
Wavequide Flange UG599/U UG383/U UG383/U-M UG385/U UG-387/U UG387/U-M UG387/U-M UG387/U-M
Bandwidth, GHz Full Full Full Full Full Full Full Full
ENR, dB (nom) 15 14 13 13 13 12 12 12
ENR Flatness, dB ±1.0 ±1.5 ±1.5 ±1.5 ±1.5 ±1.5 ±2.0 ±2.5
Stability, dB/°C 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01
Stability/Day, dB 0.05 0.05 0.05 0.05 0.05 0.05 0.05 0.05
Biasing Voltage, V +18…+28
Sizes, mm* 50/75 50/75 50/75 50/75 50/60 50/60 50/60 50/60
* Cylinder diameter/length (without isolator)

Notes:

  • Maximum operating temperature is +60 °C
  • Diode operating current is 50…100 mA.
  • A limiting value of modulation frequency is 1 kHz (external triggering).
  • Triggering signal amplitude is TTL level.
  • Bias voltage is +18 V It is possible to supply the noise source with +28 V DC biasing for the compatibility with commonly used noise meters.
  • External triggering connector is SMA female
  • ENR would be increased for narrower bandwidth. Please contact factory. 
  • For higher frequency models please contact factory.

Power supplies for input power 220 V AC/50Hz, 110 V AC/60Hz or 100 V AC/50Hz are available optionally.

For the precision control and fast modulation of the output power of the source Voltage Controlled Attenuator VCVA-XX series can be supplied optionally

How to order

Specify Model Number ISSN-XX/BW/V, where

XX  – number of waveguide standard (Ex. 10 for WR-10 and 06 for WR-06)

BW – operating bandwidth in GHz (nothing if full band)

V   – type of power supply: 18 or 28 if external power supply +18 V DC or +28 V DC of customer’s lab will be used (specify voltage), 110 or 220 if external 110 V AC or 220 V AC power supply is requested together with noise source

Examples

ISSN-10/28 ( W-band noise source with output waveguide WR-10, full band 75-110 GHz, external power supply +28 V DC not requested

ISSN-06/110-140/220 ( D-band noise source with output waveguide WR-06, operating frequency 110-140 GHz, external 220VAC power supply requested as well