E4416A_E4417A EPM-P Series Power Meters and E-Series E9320 Peak and Average Power Sensors.pdf - 第14页

Find us at www.keys ight.com Page 14 Peak Flatness The peak flatness is the f latness of a peak - to - average ratio mea surement for variou s tone - separatio ns for an equal magnitude t wo - tone RF input . Figures 6, …

Find us at www.keysight.com Page 13

Figure 4. Typical power linearity at 25 °C for the E9323A and E9327A 5 MHz bandwidth sensors, after zero and

calibration, with associated measurement uncertainty.

Power range –30 to –20 dBm –20 to –10 dBm –10 to 0 dBm 0 to +10 dBm +10 to +20 dBm

Measurement uncertainty

0.9%

0.8%

0.65%

0.55%

0.45%

Figure 5. Relative mode power measurement linearity with an EPM-P series power meter, at 25 °C (typical).

Figure 5 shows the typical uncertainty in making a relative power measurement, using the same power

meter channel and the same power sensor to obtain the reference and the measured values. It also

assumes that negligible change in frequency and mismatch error occurs when transitioning from the

power level used as the reference to the power level measured.

Find us at www.keysight.com Page 14

Peak Flatness

The peak flatness is the flatness of a peak-to-average ratio measurement for various tone- separations

for an equal magnitude two-tone RF input. Figures 6, 7 and 8 refer to the relative error in peak-to-

average measurement as the tone separation is varied. The measurements were performed at –10 dBm

average power using an E9288A sensor cable (1.5 m).

Figure 6. E9321A and E9325A Error in peak-to-average measurements for a two-tone input (high, medium, low and

off filters).

Figure 7. E9322A and E9326A error in peak-to-average measurements for a two-tone input (high, medium, low and

off filters).

Find us at www.keysight.com Page 15

Figure 8. E9323A and E9327A error in peak-to-average measurements for a two-tone input (high, medium, low and

off filters).

Calibration Factor (CF) and Reflection Coefficient (Rho)

Calibration Factor and Reflection Coefficient data are provided at frequency intervals on a data sheet

included with the power sensor. This data is unique to each sensor. If you have more than one sensor,

match the serial number on the data sheet with the serial number of the power sensor you are using.

The CF corrects for the frequency response of the sensor. The EPM-P series power meter automatically

reads the CF data stored in the sensor and uses it to make corrections.

For power levels greater than 0 dBm, add to the calibration factor uncertainty specification:

•

± 0.1%/dB (for E9321A and E9325A sensors),

•

± 0.15%/dB (for E9322A and E9326A sensors) and

•

± 0.2%/dB (for E9323A and E9327A sensors)

Reflection Coefficient (Rho) relates to the SWR according to the formula:

•

SWR = (1 + Rho)/(1 – Rho)

Maximum relative uncertainties of the CF data are listed in Table 7. The uncertainty analysis for the

calibration of the sensors was done in accordance with the ISO Guide. The uncertainty data, reported

on the calibration certificate, is the expanded uncertainty with a 95% confidence level and a coverage

factor of 2.