Radio Noise Measurement and Related Standards Akira SUGIURA Tohoku Univ., JAPAN
Contents (1) Measuring receivers: Conventional instrument Response to various signals Future instruments for digital communication (2) Radiated noise measurements: Measuring antennas Antenna calibration Standards for radiation measurement (3) Long term city noise measurements in Japan
Measuring Receivers (1) Conventional instrument (2) Response to various signals (3) Future instruments for digital communication
Radio noise measurements Antenna Radiated Noise EMI meas. receiver Conducted Noise LISN
EMI measuring receiver (1) Below 1 GHz, the measuring instrument is like an AM receiver, but the detector function is different. The fundamental concept was proposed by Aggers, et al. in 1940 .
Below 1 GHz, various detectors are used. EMI measuring receiver (2) Below 1 GHz, various detectors are used. Burrill made experiments to determine Tc and Td in 1942. Noises: electric razor, dc commutator machine, relays Victim: AM broadcast receivers (Listener =30)
EMI measuring receiver (3) Above 1 GHz, the spectrum analyzer is employed. CISPR std. IF Bandwidth: 1 MHz Video Bandwidth: <1 MHz for weighting Detector: envelope + peak display
EMI measuring receiver (4) Recurrent pulse response (0.15-30 MHz)
Response to recurrent pulses (1)
Response to recurrent pulses (2)
Response to recurrent pulses (3)
Amplitude Probability Distr. APD(Ek)=[S Di(Ek)] / To EMI measuring instrument for digital communication Amplitude Probability Distr. APD(Ek)=[S Di(Ek)] / To
APD measurement (1) Freq. scan stopped. Various circuits developed for APD Ref. Signal Ek Clock Counter for Ek Comparator Example
Peak, QP, RMS, Av in APD Spauling, Disney OT report 74-38,1974
Degradation in comm. system caused by noise (1) Switching-type oven: ON Trans-type oven: ON 10 -7 -6 -5 -4 -3 -2 -1 -10 20 30 40 Prob. (noise env. > abscissa) Input voltage [dBμV] Antenna gain : 0 dBd d = 1 m d = 3 m Microwave oven: OFF 40 10 -7 -6 -5 -4 -3 -2 -1 20 30 Bit error rate Signal input [dBμV] Signal: non burst Time: 10 s/data d =1 m d = 3 m APD of noise envelope from microwave ovens BER characteristics of PHS Y. Yamanaka, IEICE Japan, J79-B-11,pp.827-834, 1996
Radiated Noise Measurements (1) Measuring antennas (2) Antenna calibration (3) Standards for radiation measurement
Radiated noise measurements
Antenna factor E [dBmV/m] = V [dBmV] + AF [dB(1/m)] Za is affected by the ground. 7 E [dBmV/m] = V [dBmV] + AF [dB(1/m)]
Half-wave tune dipole antenna (1) Free-space AF Height dependence of AF 8
Biconical antenna Ant. factor & its height dependence K. Gyoda, Y. Yamanaka, et al., IEICE Trans. Commun.,E78-B, pp.268-272, 1995 9
Log-periodic dipole array antenna Ant. factor & its height dependence T. Nagai, et al., IEICE (Japanese),J81-B-II, pp. 624-631, 1998. 10
Log-periodic dipole array antenna H-plane Directivity T. Nagai, et al., Trans. IEICE (Japanese),J81-B-II, pp. 624-631, 1998. 10a
Bi-log antenna Antenna factor variation Directivity Fujii, et al., Trans. IEICE (Japanese), J84-B, pp.272-282, 2001
Antenna positioning (1) phase center location (2) directivity (3) near field effects T. Nagai, et al., Trans. IEICE (Japanese),J81-B-II, pp. 624-631, 1998.
Antenna calibration (1) < Standard Antenna Method > <Reference Antenna Method>
Antenna calibration (2) < Standard Site Method (ANSI C63.5-1999) >
in radiated emission measurements ? What is to be measured in radiated emission measurements ? 1. accurate E-field ? antenna: wide variety calibration: for various freq., heights & polarization others: directivity to be limited 2. accurate received voltage ? antenna: standardized CISPR reference antenna calibration: not required but correlation should be checked
City Noise Measurements Long-term City Noise Measurements in Japan 1971-1982
Environmental radio noise (1) Spauling & Disney measured the APD (B=10 kHz) of man-made noise below 1 GHz at 103 points in USA to evaluate the rms values. OT report 74-38,1974 & CCIR report 258-3
Long-term city noise meas. (1) Radio Regulatory Bureau, Ministry of Posts and Telecomm. Japan Quasi-peak measurements Frequency and Years (1) VHF band: 50, 100, 200 MHz 1971, 1974, 1977, 1980 (2) MF band: 0.5, 1.0, 1.5 MHz 1972, 1975, 1978, 1981 (3) UHF band: 400, 600, 850 MHz 1973, 1976, 1979, 1982 Environments Areas: Japan (Business, Residential, Rural) City Size: 22 cities ( including Tokyo)
Noise Power vs. Population Long-term city noise meas. (2) Noise Power vs. Population
Long-term city noise meas. (3) B: business T: total L: residential G: green zone
Long-term city noise meas. (4) B: business T: total L: residential G: green zone
Long-term city noise meas. (5) Correlation is ambiguous because (1) near-by cars dominates the measurement results (2) quasi-peak function masks many lower noises
Long-term city noise meas. (6) Noise level changes in accordance with daily life pattern and activities
City noise noise waveform APD Yamanaka, et al., Trans. IEICE, E80-B, pp.663-669,1997
Airborne noise measurement 1980, Tokyo area, monopole (99 MHz), B=80kHz, h=600, 750, 1050, 1440m
Survey of man-made noise Existing data on man-made noise: in quasi-peak values below 1 GHz at outside areas like road, highway, park before 20 years ago only a few data available in rms values Hence, measurements are needed for future communication systems in APD above 1 GHz at indoor environment as well as outdoors
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