HIGH-FREQUENCY QUANTITIES LABORATORY
     
RF Voltage RF and microwave power
                   
     
RF VOLTAGE
                   
      Quantity - RF Voltage.
      Unit - Volt (V).
      Tasks of the laboratory
      The main task of laboratory is the realisation of RF Voltage standard unit and its traceability to working standards.
      International comparisons
      GT-RF 92-6 (CCEEM.RF-K4.CL), HF 2.
    Available metrological services
      Calibration of secondary standards of I. and II. orders within the range from 1 µV to 1 V and the frequency range from 50 kHz to 1 GHz respectively from 2 V to 30 V and frequency range from 50 kHz to 30 MHz. Ranges and uncertainties are dependent on frequency and amplitude.
      Calibration of the HF voltage measuring instruments for industrial use and for the telecommunications.
     
Range (V) Frequency (MHz) Expanded Uncertainty (k=2)
0.1 ÷ 2 0.05 ÷ 10 0.02 ÷ 0.2
10 ÷ 200 0.2 ÷ 0.6
200 ÷ 1000 0.6 ÷ 1.6
10-5 ÷ 0.1 0.05 ÷ 1000 2 ÷ 8
2 ÷ 30 0.05 ÷ 30 0.2 ÷ 1
      Methods of measurement:
      - the HF primary voltage standard in the frequency range from 50 kHz to 1000 MHz was developed at the SMU. The unit is derived from thermal effects of RF power and the physical model of scanning element (thermistor). Elements of model are determined by length variation of thermistor leads and nominal value of resistance of thermistor. The real value of RF voltage in a given level of RF wiring is determined by calculation on the base of stated elements of thermistor equivalent scheme. It is calculating standard based on linear measures and DC quantities;
      - other method of determination of RF voltage values is based on primary standards of RF power and RF impendance. The obtained value are verified in international comparison measurements with NMI's;
      - the scale of RF voltage unit, which is transfered by secondary standards at meters in accordance with customer's demands is derived by a suitable method providing the linearity of transfer;
      - the thermistor and thermocouple mounts measurements, e.g. firms Fluke, Hewlett-Packard, high frequency wide-band and selective voltmeters, spectral analysers and oscilloscopes, measurement of ascending level of signal generators in the range of 10 kHz up to 1 GHz are carried out for purposes of industry, telecommunications and defence. The uncertainty range is in accordance with a frequency range and nominal value of measured power from 0.05 % to 10 %.
       
    Instruments in use
      The working standards within a voltage range from 100 mV to 1 V and a frequency range from 50 kHz to 1 GHz. The standard mounts for voltage ranges up to 30 V and frequency ranges to 30 MHz.
       
     
Contact
Mr. Ivan Petráš Ing. Peter Vrabček, PhD. Mrs. Katarína Mokrošová
phone: + 421 2 60294 243 phone: + 421 2 60294 385 phone: + 421 2 60294 234
e-mail: petras@smu.gov.sk e-mail: vrabcek@smu.gov.sk  
     
                   
     
RF AND MICROWAVE POWER
       
      Quantity - RF and Microwave power.
      Unit - mW, W.
      Tasks of the laboratory
      The main task of the laboratory is the realisation of RF and microwave power primary standard unit and its traceability to working standards.
      International comparisons
      EUROMET No. 393.
    Available metrological services
      Calibration of secondary standards of I. and II. orders from 10 µW to 1000 mW in the frequency range from 10 MHz to 18 GHz (coaxial line of 50 , 7/3 mm), ranges and uncertainties are dependent on frequency and power. Calibration of secondary standards of I. and II. orders from 1 mW to 10 mW in the frequency range from 8.2 GHz to 12.4 GHz (waveguide). Calibration of RF power measuring instruments for purposes of industry and telecommunications.
     
Range (mW) Frequency (GHz) Expanded Uncertainty (k=2) Remark
1 ÷ 10 8.2 ÷ 12.4 1.2 waveguide
1 ÷ 1000 0.01 ÷ 1 2.5 ÷ 3.5 coaxial 7/3
10-5 ÷ 1 0.01 ÷ 18 3.5 ÷ 4.5 coaxial 7/3
1 ÷ 200 0.01 ÷ 18 2.5 ÷ 3.5 coaxial 7/3
      Methods of measurement:
      - primary standards of RF power in a frequency range from 10 MHz to 18 GHz were devepoped at the SMU. Nominal value of measured RF power is 10 mW at a primary level. The power unit is derived from comparison of RF thermal effects to the equivalent effects of given DC quantity, which value is possible to be determined with a very low uncertainty. The scale of RF power unit, which is transfered by secondary standards at meters in according with customer's requirements, is derived by a suitable method providing a linearity of transfer. Thermistor, baretter and thermocouple mounts to the power meter of different producers in the range from 10 MHz to 18 GHz in accordance with customer's demands from 10 MHz to 18 GHz in the coaxial line resp. from 8.2 GHz to 12.4 GHz in waveguide.
      The range of calibrated power is from 100 µW up to 1000 mW (up to 1 GHz only) at higher frequencies to 70 mW. The combinated standard uncertainty of measurement of standard mounts according to frequency range and nominal value of RF power range is from 0.3 % to 1.2 %.
       
    Instruments in use
     
Working standards in a range from 1 mW to 10 mW in a frequency range from 10 MHz to 18 GHz in the coaxial line of 7/3 mm. Standard power measuring mounts for an X-band waveguide.
       
     
Contact
Mr. Ivan Petráš Ing. Peter Vrabček, PhD. Mrs. Katarína Mokrošová
phone: + 421 2 60294 243 phone: + 421 2 60294 385 phone: + 421 2 60294 234
e-mail: petras@smu.gov.sk e-mail: vrabcek@smu.gov.sk e-mail: mokrosova@smu.gov.sk