Report ITU-R TF.2487-0 (09/2021) Protection criteria for systems in thestandard frequency and time signal services
Foreword
Policy on Intellectual Property Right (IPR)
Scope
Keywords
1 Introduction
2 Recommendation ITU-R P.372 environmental noise
3 Information on the UK SFTS service
     3.1 The National Physical Laboratory MSF signal
     3.2 ON/OFF keying Gaussian noise-to-signal requirements
          3.2.1 ON/OFF keying standard detection by threshold
          3.2.2 Derivation of bit error probability and overall error probability for ON/OFF keying
          3.2.3 Gaussian theory statistics
          3.2.4 Summary of ON/OFF keying signal to Gaussian interferer statistics
     3.3 Lock up times with “N bits correct sequence over 1 minute”
          3.3.1 Signal structure for decoding – the need for a multiple bits correct sequence
          3.3.2 Actual MSF lock up performance and signal to noise ratios
     3.4 Typical receiver characteristics for domestic OEM receiver units
          3.4.1 Introduction
          3.4.2  Structure of the tuner
          3.4.3 Antenna selectivity curve
          3.4.4 Data parameters from OEM manufacturers
          3.4.5 Background information on ferrite rod antennas
          3.4.6 Antenna pickup sensitivity
          3.4.7 Summary of typical values from data sheets
          3.4.8 MSF signal levels versus distance from transmitter
          3.4.9 Output signal levels for the antenna based on OEM datasheet
          3.4.10 Required Integrated circuit tuner/detector module input
     3.5 Amplifier
     3.6 Narrow band filter
     3.7 Detector
4 Information on the US SFTS service
     4.1 WWVB modulation and time code format
          4.1.1  Coverage area for WWVB
     4.2 AM signal analysis
          4.2.1 Detection
          4.2.2 Measurements
     4.3 WWVB phase modulation
          4.3.1 Binary phase shift keying modulation
          4.3.2  Bit error rate analysis
     4.4  Bit-designation in the transmitted frame
          4.4.1  Representation of timing information using a known sequence
          4.4.2 Efficient representation of time information
          4.4.3 Linear coding of time word
          4.4.4 Encoding of the additional information fields
          4.4.5 Linear coding for DST and leap second indicators
          4.4.6 Non-linear coding of DST schedule word
     4.5 Reception of WWVB in the presence of WPT operating on-frequency
          4.5.1 AM envelope-detector-based receiver
          4.5.2  Detection limits for an on-frequency jammer
     4.6 Reception of WWVB in the presence of WPT operating off-frequency
          4.6.1 Additive noise tolerance for WWVB AM reception
5 Information on the German SFTS service
     5.1 Description of the German SFTS service DCF77
          5.1.1 Amplitude Modulation (AM)
     5.2 Reception of DCF77 and expected field strength
     5.3 Signal properties and reception experiences
          5.3.1  AM decoding Example 1
          5.3.2 AM and PM reception with a quadrature receiver
          5.3.3 Results of further studies on DCF77 reception
          5.3.4 DCF77 reception under everyday conditions
     5.4 Considerations and studies about WPT and DCF77 coexistence
          5.4.1  Comparison of ETSI WPT operations regulations to DCF77 reception
          5.4.2 Summary of studies on WPT operations with DCF77 reception by standard receivers
6 Information on the Japanese SFTS service
     6.1 Outline of the JJY service
     6.2 Example characteristics of receivers
     6.3 Results of the study of impact to the clock/watch devices receiving SFTS from WPT for EV
          6.3.1 Potential interference from WPT
          6.3.2 Discussion of estimated required charging time of EV
          6.3.3 Probability of overlap with clock synchronization and charging of WPT-EV
          6.3.4 Considerations on the impact to the clock/watch devices receiving SFTS from WPT for EV
          6.3.5 Summary of impact study for WPT for EV in Japan
7 Information on the Chinese SFTS services
     7.1 BPC
     7.2 BPL time signal emission
          7.2.1 Overview of BPL service
          7.2.2 Technical description of BPL
          7.2.3 BPL receivers
     7.3 BPM Time Signal Emission
          7.3.1 Overview of BPM service
          7.3.2 BPM broadcast programme
          7.3.3 Station identification format
          7.3.4 Time signals format
          7.3.5 Broadcast time, Carrier power and antenna type
8 Information on the Russian SFTS services
     8.1 RBU and RTZ Service
          8.1.1 RBU protection limits
          8.1.2 Form of the reference frequency and time signals
          8.1.3 Information coding, transmitted as part of DXXXW signals
     8.2 RWM service
          8.2.1 Form of the reference frequency and time signals
          8.2.2 The hourly programme of the radio station RWM
9 Information on the French SFTS service
     9.1  Introduction
     9.2 Description of the testing facility
     9.3 Measurement protocol and results
          9.3.1 Step 1 – Calibration of the TEM cell at 162 kHz with a reference antenna
          9.3.2 Step 2 – Verifying the linearity of the measurement device
          9.3.3 Step 3 – Determination of the synchronisation time of radiosynchronization receivers in a noise-free environment and in the absence of misalignment
          9.3.4 Step 4 – Sensitivity test of radiosynchronization receivers in a noise-free environment and in the absence of misalignment
          9.3.5 Step 5 – Sensitivity test of radiosynchronization receivers in a noise-free environment and in the presence of misalignment
               9.3.5.1 Misalignment on a device with a single antenna (ALS162 demonstrator)
               9.3.5.2 Misalignment on devices with orthogonal antennas (Cristalys Date)
          9.3.6 Step 6 – Calibration of the noise field with a reference antenna
          9.3.7 Step 7 – Sensitivity test of radiosynchronization receivers in a noisy environment and in the absence of misalignment
               9.3.7.1 Reference noise field at 26.5 dBµV/m
               9.3.7.2 Reference noise field at 35.7 dBµV/m
          9.3.8 Step 8 – Sensitivity test of radiosynchronization receivers in a noisy environment and in the presence of misalignment
     9.4 Summary
10 Conclusion