Through continuous research, development and improvement of measurement methods and systems we provide clients with a comprehensive and efficient calibration service traceable to the national standards which are accepted internationally. The principal electrical parameters on which our radio frequency and microwave measurements are founded are high frequency voltage, power, attenuation and impedance. Calibration services traceable to national standards are provided for these quantities. Specialised equipment is maintained for verifying equipment used for EMC measurements.
Calibration services are available for antennas, attenuators, EMC equipment, field meters, impedance and reflection coefficient, phase shifters, power sensors and meters, and thermal voltage converters. Click here:
Before consigning an instrument for calibration always consult us to discuss your requirements. For further information contact calibration.coordinator@measurement.gov.au.
NMI's primary standard of attenuation is a waveguide-below-cutoff attenuator operating at 30 MHz. Attenuation at other frequencies is established using a heterodyne technique. Attenuation can also be measured using a network analyser, usually at lower cost.
Measurements can be made over a frequency range of 30 MHz to 40 GHz and an attenuation range of 0 to 100 dB.
Measurements can be made in the waveguide frequency-bands 2 to 4 GHz, 8.2 to 12.4 GHz, 12.4 to 18 GHz, 18 to 26.5 GHz and 26.5 to 40 GHz, and an attenuation range of 0 to 100 dB.
Attenuation measurements can be carried out using an Automatic Network Analyser. This is an efficient method for covering a large number of measurement frequencies at lower cost than the techniques described in the above sections, but it results in larger measurement uncertainties. If necessary, NMI staff should be consulted regarding the appropriate technique for measurements. On request, frequency plots can be attached to the measurement report.
Loop antennas are calibrated using a coaxial configuration. Antenna factors can be measured between 9 kHz and 30 MHz.
Dipole, bi-conical, log-periodic and similar antennas are calibrated outdoors using a three antenna method at frequencies between 30 MHz and 1 GHz. Free-space antenna factors, and antenna factors for horizontally polarised antennas at fixed height above a flat reflecting plane, can be measured.
Standard gain pyramidal horn antennas are calibrated in a microwave anechoic chamber using a three antenna method. The gain of standard gain horns can be measured at frequencies between 2.45 and 18 GHz in waveguide systems or coaxial systems. Measurements at other frequencies may be available by special arrangement.
The free-space antenna factors of EMC antennas, such as dipoles, biconicals, log-periodic arrays and double-ridged horn antennas, in the frequency range from 1 GHz to 6 GHz, are determined by using a three-antenna method in a microwave fully anechoic chamber. At each frequency, an averaging process to remove the chamber reflections is applied to the measured antenna factors at different separation distances over a quiet zone.
Electric field strength meters are calibrated in a tapered TEM cell at frequencies between 10 MHz and 1 GHz, and at field strengths from 10 to 61 V/m. Measurements at lower field strengths may be available by special arrangement.
Radiation hazard meters are calibrated in a microwave anechoic chamber at the frequency of 2.45 GHz and power flux density levels from 2 W/m2 to 1000 W/m2.
Impedance and reflection coefficients are measured using a network analyser, which in turn has been calibrated using precision transmission lines whose dimensions are accurately known.
Frequency-domain and time-domain measurements of reflection and transmission coefficients can be measured in coaxial systems over the frequency range 0.05 to 40 GHz. In waveguide systems, the measurements can be carried out in the waveguide frequency bands 2.2 to 3.3, 2.6 to 3.95, 3.95 to 5.85, 4.9 to 7.05, 5.85 to 8.2, 8.2 to 12.4, 10.0 to 15.0, 12.4 to 18.0, 18.0 to 26.5 and 26.5 to 40.0 GHz. On request, frequency plots may be attached to the report.
NMI maintains as its primary standard a set of reference sensors, calibrated in a micro-calorimeter which provides traceability back to the Australian standards. Clients' power sensors (including thermistor mounts) are calibrated against the reference sensors.
Calibration factors for power sensors and transfer mounts can be measured between 100 kHz and 40 GHz at power levels up to 10 mW.
Automated measurement of calibration factors is available for terminating power sensors with Type-N or APC-7 connectors in the frequency range 1 to 18 GHz, and for waveguide power sensors in the frequency range 18 to 40 GHz. For automated measurements at a power level of 1 mW, the fee per additional frequency is lower than for non-automated measurements.
Thermoelectric power sensors require calibration at the reference frequency, usually 50 MHz.
For other connector types and power levels, additional fees may apply.
The linearity of power meters can be measured at power levels up to 100 mW at a frequency of 50 MHz. Reference 1 mW power sources can also be calibrated.
Thermal voltage converters are calibrated against one of a reference set. Measurements can be made of the rf-dc difference of thermal converters at frequencies of 1, 3, 10, 30, 50, 70 and 100 MHz in the range from 0.25 to 10 V. Measurements may be available at higher voltages or higher frequencies by special arrangement.
Measurements can be made in the waveguide frequency band 8.2-12.4 GHz on a regular basis and in other bands by arrangement.
Coaxial phase shifters can be calibrated at 30 MHz.
Various items of EMC measuring equipment can be calibrated and/or verified in accordance with the requirements of Australian and international EMC equipment standards. Calibration services for antennas are listed above. Services for other EMC measurement equipment are listed below.
Single-phase and three-phase artificial mains networks can be calibrated and verified in accordance with CISPR 16-1. The AMN impedance can be verified and the radio frequency voltage division factor can be calibrated from 9 kHz to 30 MHz. The 50 Hz voltage drop and saturation properties to 32 A can be verified.
The transfer impedance can be calibrated and the insertion impedance verified for current probes used for conducted emission testing from 150 kHz to 30 MHz.
ESD generators can be verified in accordance with IEC 61000-4-2. The rise time, peak current, current at 30 ns and current at 60 Ns can be verified at the 2 kV, 4 kV, 6 kV and 8 kV voltage settings.
The transfer conductance of injection probes used for immunity testing from 150 kHz to 30 MHz can be calibrated.
The insertion loss can be calibrated and the impedance verified in accordance with CISPR 16-1 for absorbing clamps used for disturbance power measurements from 30 MHz to 300 MHz.