INSTRUCTION SHEET WIDEBAND POWER SENSOR MODEL 5012 ©Copyright 2008 by Bird Electronic Corporation Instruction Book P/N 920-5012 Rev.
Description The Bird 5012 Wideband Power Sensor (WPS) is a Thruline sensor that can measure average, peak, or burst power, VSWR, crest factor, and Complementary Cumulative Distribution Function (CCDF). It can be used with the Bird 5000-EX Digital Power Meter (DPM) and the Bird Virtual Power Meter Software (VPM). NOTE: Firmware upgrades extending the WPS’s capabilities may be periodically released.
Zeroing Sensor Over time, the sensor’s “zero value” (reading with no applied RF power) can drift, making all readings inaccurate by this value. For example, if the zero value is –0.02 W, measuring a 50 W signal will give a reading of 49.98 W, a 0.04% error. Measuring a 1 W signal will give a reading of 0.98 W, a 2% error. If the drift would be a significant error, rezero the sensor: y Make sure the sensor has reached a stable operating temperature. y Make sure no RF power is applied to the sensor.
VSWR VSWR measures the relation between forward and reflected average power. The Bird Wideband Power Sensor calculates the VSWR from the Forward and Reflected Average Power measurements. Rho and Return Loss are also the same measurement, but in different units: Rho (µ) = PR ⁄ PF , , and The health of the feedline and antenna systems can be monitored using VSWR measurement under full power operating conditions.
Peak Envelope Power Peak power measurements detect amplitude changes as a signal modulates the carrier envelope. The WPS operates in an asynchronous cycle: 300 ms of waveform sampling followed by a 50 ms reset period. The peak power is then displayed and the cycle repeats. The display therefore updates about three times per second. Transmitter overdrive can be detected with peak measurements. Common problems are overshoot at the beginning of burst packets, amplitude modulation, and excessive transients.
Crest Factor Figure 4 Crest Factor 100 W 10 dB CDMA Signal 100 W Peak 10 W Ave 50 W Peak Envelope Power Average Power 0W Crest factor (CF) is the ratio of the peak and average powers, in dB. The WPS calculates the Crest Factor from the Forward Peak and Average Power measurements. Crest factor is becoming one of the most important measurements as communication systems move into the digital age. For CDMA and similar modulation types the CF may reach 10 dB.
Specifications Sensor Characteristics Frequency Range 350 MHz to 4 GHz RF Power Range 0.15 W – 150 W Average, 4 – 400 W Peak Maximum Power See Figure 7 on page 9 Impedance, Nominal 50 ohms Insertion Loss, Max: 0.35 – 1 GHz 1 – 4 GHz 0.05 dB 0.1 dB Input VSWR, Max: 0.35 – 2.5 GHz 2.5 – 4 GHz 1.05:1 1.10:1 Directivity, Min: 0.
Match Measurement Measurement Range: Return Loss Rho (ρ) VSWR 0 to 23 dB 0.07 to 1.0 1.15 to 99.9 Forward Power, Min 0.5 W Measurement Uncert. See Figure 6 on page 8 Figure 6 Match Measure Uncertainty Match Measurement Uncertainty 4 Uncertainty (dB) Above 3 GHz Below 3 GHz 2 0 –2 –4 –6 0 –5 –10 –15 –20 –25 Return Loss (dB) Peak Envelope Power RF Power Range 4.0 – 400 W* Measurement Uncert.: burst width > 200 µs 1 µs < b.w. < 200 µs burst width < 1 µs burst width < 0.
Figure 7 Max. Peak Power Maximum Peak Power Peak Power (Watts) 1000 VSWR = 1 VSWR = 1.5 VSWR = 3 400 100 0.3 1 Frequency (GHZ) Burst Average Power Power Range 10 – 150 W average Burst Width 1 µs – 50 ms Repetition Rate, Min 15 Hz Duty Cycle (D) 0.001 – 1 (D = Burst Width / Period) Measurement Uncert. ± (6% of reading + 0.05/D W)* * Above 35 °C or below 15 °C add 3% Crest Factor RF Power Range 4 – 150 W Measurement Uncert.
Physical and Environmental Specifications Temp, Operating –10 to +50 °C (+14 to +122 °F) Temp, Storage –40 to +80 °C (–40 to +176 °F) Mechanical Shock and Vibration MIL-PRF-28800F class 3 Humidity, Max 95% (non-condensing) Altitude, Max 15,000 ft. (4,500 m) Dimensions, Nominal 4.75” x 4.6” x 1.3” (121 x 117 x 33 mm) Weight, Max 1.2 lb. (0.
RF POWER INPUT OUTPUT WIDEBAND POWER SENSOR MODEL 5012 350 – 4000 MHz 4.6" (116 mm) STATUS 12VDC RS232 USB METER RS-232 1.3" (33 mm) TO PC TO DPM 3.
