Agilent Technologies manual Agilent E-Series E9300 Power Sensors in Detail

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The Agilent E-Series E9300 Power Sensors in Detail

Most power sensors used for measuring average power employ either thermocouple or diode technologies. Diode based sensors frequently rely on the application of correction factors to extend their dynamic range beyond their square law response region, typically -70 dBm to -20 dBm. However, while this technique achieves wide dynamic range capability, it is limited to continuous wave (CW) signals outside the square law region. Modulated signals must be padded down or at low levels, with their average and peak power levels within the diode square law region, to be measured accurately. Accurate, average power measurement of high level signals carrying modulation cannot be obtained using a CW correction factor technique. Specialized modulation sensors provide accurate measurements but are bandwidth limited.

The HP E-series E9300 power sensors are true average, wide dynamic range RF microwave power sensors. They are based on a dual sensor

diode pair/attenuator/diode pair proposed by Szente et. al. in 19901. Figure 2
shows a block diagram of this technique.		￿
	Low Sense
		Lower Range
		(-60 dBm to -10 dBm)
RF in		Low Sense±±￿
	High Sense
		Upper Range
		(-10 dBm to +20 dBm)
	High Sense

Figure 2 Simplified Block Diagram of Diode Pair/Attenuator/Diode Pair

This technique ensures the diodes in the selected signal path are kept in their square law region, thus the output current (and voltage) is proportional to the input power. The diode pair/attenuator/diode pair assembly can yield the

1. US Patent #4943764, assigned to Agilent Technologies

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