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SPECTRUM ANALYSIS: FREQUENCY RESOLUTION AND INTEGRATION.

If you need to determine the field strength due to individual wireless services, service providers, or even a single channel, the frequency resolution must be fineenough for the job. The SRM lets you analyze eachchannel separately in the mobile phone or DECT band without any trouble. If you want to know the total power level in the frequency band, you don’t have tomake a new measurement. The integration functionwill give you the value. Pagers switch on and off without warning, communi-cations channels are used sporadically, so the frequency spectrum is constantly changing. In “Time Analysis”mode, the SRM can record the variation with timedown to one-second accuracy, so you can see how individual channels behave over a period of time. With “Time Controlled Storing” (option), you can pre-program a specific starting time and measurementduration. Most standards prescribe time averaging over a six-minute period to determine exposure levels for thehuman body. The SRM does this automatically, too, regardless of the observation period displayed on thescreen. SPECTRUM ANALYSIS
How high is the total power level? The integration range can be setjust as easily as the zoom range. The numerical result is displayed automatically at the top right of the measurement window.

SPATIAL AVERAGING:SPATIAL RESOLUTION AND AVERAGING FUNCTIONS.TIME ANALYSIS: TIME RESOLUTION AND TIME AVERAGING.

Close to transmitter arrays and in reflecting spaces, thefield strength is not distributed evenly. There are defi-nite “hot spots” and minima. To realistically determinehow humans are affected, various standards require spatial averaging over a volume corresponding roughlyto the human body.The “Spatial Averaging” function of the SRM (option) makes this easy. The measuring antenna is simplymoved along the desired path in space for continuousaveraging. For discrete averaging, pressing a button adds the measured value at each required point inspace. The SRM then averages the values automaticallyand displays the resulting average value according to IEEE as the end result, for example. MAXIMUM VALUESAND AVERAGES. Where is the field strengthhighest in the room? At what frequency? When dopeak values occur, and how longdo they last? The SRM shows all thisdirectly. And if you need to know theaverage values instead, the SRM showsthem, too. SPATIAL AVERAGING TIME ANALYSIS
How high is the average field exposure determined over the volume ofthe human body? The SRM averages several spatial values continuouslyor discretely and displays the result directly at the end of the procedure. Past values can be read out using the marker. The so-called duty cycle function automatically determines the ratio of average to maximumpower (Pavg/Pmax). THE SRM FROM NARDA: ANALYZES, AVERAGES, AND INTEGRATES. IN FREQUENCY, SPACE, AND TIME. 1617