Spectrum Analyzer Measurement Guide : Spectrum Analyzer : Field Strength
Field Strength
Required Equipment
Portable Antenna for which antenna factors or antenna gain and bandwidth data are available.
1. Press the Shift key then the Measure (4) key. Then press the Power and Bandwidth submenu key, and press the Field Strength submenu key followed by pressing the On/Off submenu key so that On is underlined.
2. Press the Antenna submenu key to display the loaded antenna profiles with their model number and frequency range. Use the up or down arrow keys or the rotary knob to select the desired antenna. Press the Enter key to select or ESC to cancel.
Select an antenna from the standard list available or use the Antenna Editor feature of Anritsu Master Software Tools to define a custom antenna and upload the antenna information to the antenna list.
When the Field Strength measurement is enabled, an additional plot is shown at the bottom of the display indicating the selected antenna factor over the currently set frequency span. The field strength measurement is automatically adjusted for this antenna factor.
Field Strength Measurement Display
3. Connect the antenna to the RF In port.
4. Press the Freq main menu key, press the Center Freq submenu key, and enter the center frequency.
5. Press the Span main menu key. Set the span wide enough to include the primary channel bandwidth and upper and lower channel bandwidths. At least a portion of the span has to include a frequency within the antenna’s specified range.
6. Press the BW main menu key and verify that Auto RBW and Auto VBW are On.
7. To change the units of measurement, press the Amplitude main menu key, then press the Units submenu key and press dBm/m2, dBV/m, dBmV/m, dBµV/m, Volt/m, Watt/m2, dBW/m2, A/m, dBA/m, or Watt/cm2. The instrument automatically adjusts the measurement by the antenna factors selected. Marker values are displayed in the same units as selected for amplitude.