IEEE 475:2000 pdf download.IEEE Standard Measurement Procedure for Field Disturbance Sensors 300 MHz to 40 GHz.
IEEE 475 defines test procedures for microwave field disturbance sensors to measure radio frequency (RF) radiated field strength of the fundamental frequency. harmonic frequencies, near field power flux density. and nonharmonic spurious emissions of sensors operating within the frequency range of 3(X) MHz to 40 0Hz.
Field disturbance perimeter protection systems that employ a balanced transmission line around the property being protected are not covered by this standard.
1.2 Applications
Specific types of field disturbance sensors to which this standard applies are as follows:
a) RF intrusion detector
b) Production line counter detector
c) Anti-shoplifting detector
d) Level sensor
1.3 Description
1.3.1 Field disturbance sensor
A field disturbance sensor is a device that employs a highly localized source of RF energy to detect the motion or presence of an object in the vicinity of the source, and in which the emitter and receiver (or detect()r) are essentially at the same point, that is. a space-protected system.
1.3.2 Characteristics
A typical single channel microwave field disturbance sensor operates at a nominal radiated center frequency of 0.915 GHz, 2.450 GHz, 5.800 GHz. 10.525 GHz, or 24.125 GHz. It commonly employs a Gunn-type diode as a microwave oscillator, which is mounted in a waveguide cavity and coupled to a horn antenna or other directional radiator. It establishes an RF field which, when perturbed by the motion of an intruder or reflecting object in this field, causes a change (doppler shift) in the frequency of the microwave signal. The sensor’s receiver accepts a signal coupled directly from the internal oscillator and the external signals reflected from the illuminated area. If the microwave frequency of the reflected signal differs from that of the internal oscillator, this small difference in frequency is detected, amplified, and used to activate an alarm or indicator.
Since area coverage requirements vary in different installations, some field disturbance sensors are provided with optional antennas offering a selection of different radiation beam widths. Some sensors emit a signal without intentional modulation, while others employ frequency, amplitude, or pulse modulation. Field disturbance sensors that contain digital processing circuitry may be classed as unintentional radiating or computing devices by the regulatory authority.
2. References
This standard shall be used in conjunction with the following publications.
ANSI C63.2-1987, American National Standard for Electromagnetic Noise and Field Strength. 10 kHz to 40 GHz—Specifications.’
ANSI C63.4-1992, American National Standard for Methods of Measurement of Radio-Noise Emissions from Low-Voltage Electrical and Electronics Equipment in the Range of 9 kHz to 40 GHz.
ANSI C63. 14-1992, American National Standard Dictionary for Technologies of Electromagnetic Compatibility (EMC), Electromagnetic Pulse (EMP), and Electrostatic Discharge (ESD).
ANSI/NCSL Z540. 1-1994, American National Standard for Calibration —Calibration Laboratories in Measuring Test Equipment — General Requirements.IEEE 475 pdf download.