Activities

The Laboratory for Time and Frequency carries out the tasks related to:

  • Realization, conservation, maintenance and improvement of the national standard for time (frequency) in Montenegro;
  • Providing metrological traceability in the field of time and frequency in Montenegro by transferring the unit of time (frequency ) from the national measurement standard to secondary and working standards of time (frequency);
  • Development of measurement methods for transferring the unit of time;
  • Calibration of measurement standards/ measuring instruments for measuring time (frequency);
  • Realization and distribution of the national time scale;
  • Participation in the calculation of TAI (Temps Atomique International) and UTC (Universal Time Coordinated) time scales;
  • Participation in inter-laboratory comparisons;
  • Defining the prescribed technical and metrological requirements for determining the type of a measuring instrument used for measuring time (frequency);
  • Verification of measuring devices used for measuring time (frequency).

National Measurement Standard

National measurement standard of time and frequency is a commercial cesium oscillator, with a frequency divided so that it generates 1 impulse/second – 1 PPS (pulse per second) at the output. Period of output impulses represents the realization of the time interval of 1 second. Oscillator at its output also generates the frequency in the value of 10 MHz.

The caesium clock is manufactured by Gillam-Fei, type 3230. The basic features of the caesium clock are:

  • Accuracy: ± 6 • 10-13;
  • Stability: ≤1 • 10-13 for a 5-day period.

Caesium clock, as a measurement standard of the unit of time and frequency realized by definition, in combination with a time transfer system, is also the source of a time scale traceable to the UTC scale. The output of the 10 MHz caesium clock is connected to the input of the TTS-5 type time transfer system manufactured by PIKTIME Systems. The TTS-5 has a 1PPS output defined as UTC (MBM) and is the source of the national time scale.

Calibration of Measurement Standards

Accredited area:

  • Measurement of frequency in the range from 1 mHz to 350 MHz;
  • Measurement of time interval in the range from 1 ns to 100 000 s;
  • Calibration of frequency meters;
  • Calibration of stopwatches;
  • Calibration of the time measurement standard.

Laboratory for Time And Frequency’s Scope of Accreditation

Verification of Measuring Instruments

Laboratory for Time and Frequency carries out examination of time and frequency measuring instruments in order to determine compliance with the prescribed metrological requirements for the purpose of verification of:

  • main clocks within the telephone exchanges;
  • traffic speed measuring instruments for moving vehicles.

Type Approval of Measuring Instruments

In order to examine compliance with the prescribed technical and metrological requirements to determine the type of a measuring instrument, the Laboratory for Time and Frequency carries out type examination for measuring instruments in the field of time and frequency measurement in accordance with the Decree on legal measuring instruments that are subject to mandatory verification or type approval (Official Gazette of Montenegro 81/09), as follows:

  • main clocks within the telephone exchanges;
  • traffic speed measuring instruments for moving vehicles.

Traceability Scheme

The Laboratory for Time and Frequency achieves its traceability through the national measurement standard for time and frequency, the cesium clock. Establishment of traceability of the measurement standard for time and frequency i.e. measurement results to the SI system is provided using the GPS method of simultaneous observation. This method is used for calculation of the relative frequency deviation of the cesium clocks in relation to the frequency of the reference laboratory, as well as for calculation of the stability of cesium clocks.

Contact

Head of Laboratory:
Goran Vukoslavović, Graduate Degree in Engineering
tel: +382 20 601 360
+382 20 601 361
fax: +382 20 634 651
e-mail: goran.vukoslavovic@metrologija.gov.me

Deputy Head of Laboratory:
Milan Perović, Spec. App.
tel: +382 20 601 360
+382 20 601 361
fax: +382 20 634 651
e-mail: milan.perovic@metrologija.gov.me