Agilent Technologies E9300 manual Measuring Tdma Signals, Power Meter and Sensor Operation

Measuring TDMA Signals

Measuring TDMA Signals

Power Meter and Sensor Operation

The voltages generated by the diode detectors in the power sensor can be very small. Gain and signal conditioning are required to allow accurate measurement. This is achieved using a 220 Hz (440 Hz in fast mode) square wave output from the power meter to drive a chopper-amplifier in the power sensor. Digital Signal Processing (DSP) of the generated square wave is used by the power meter to recover the power sensor output and accurately calculate the power level.

The chopper-amplifier technique provides noise immunity and allows large physical distances between power sensor and power meter (Agilent 11730 series cables available up to 61 metres). Additional averaging helps reduce noise susceptibility.

Achieving Stable Results with TDMA Signals

The averaging settings in the power meter are designed to reduce noise when measuring continuous wave (CW) signals. Initial measurement of a pulsed signal may appear unstable with jitter on the less significant displayed digits. With pulsed signals the averaging period must be increased to allow measurement over many cycles of the pulsed signal.

To set the averaging proceed as follows:

Note	The example shows the key labels for a single channel power meter.
	Dual channel meter are similar, adding only channel identification to
	the softkey labels.
	1. Press	System	,	Input Settings	,		. Press the	Filter	softkey to
						More
		Inputs

access the filter menu.

2.The filter setting is displayed under the Length softkey label. To change this setting first set manual mode by pressing the Mode Man Auto softkey to highlight Man .

3.Press Length and use the , , or to set the averaging you require. Confirm your entry by pressing Enter .

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