Microwave Journal
www.microwavejournal.com/articles/15193-peak-power-measurements-for-radar-emc-and-digital-mobile-communications-with-the-r-s-nrp-z81-broadband-power-sensor

Peak power measurements for radar, EMC and digital mobile communications with the R&S NRP-Z81 broadband power sensor

January 17, 2011
With the new R&S NRP-Z81 broadband power sensor, Rohde & Schwarz is expanding its product range of USB-capable power sensors. For the first time, RF detector, analog and digital signal processing as well as the entire evaluation logic of a peak power meter are combined in a compact sensor that can be directly remote-controlled via USB. By featuring a video bandwidth of up to 30 MHz and a rise time of 13 ns, the R&S NRP-Z81 allows high-resolution envelope analyses. Complete statistical analysis of a signal can be performed within only a few milliseconds. For average power measurement, it provides a dynamic range of 80 dB. The instrument's frequency range from 50 MHz to 18 GHz makes it suitable for sophisticated measurements on radar and mobile radio signals and helps to save on space and costs. The continuous development of wireless digital communications technology increases demands concerning electrical power measurement in the RF and microwave range. Advanced mobile radio standards such as 3GPP FDD or WiMAX require not only an exact determination of the average signal power but also a detailed envelope analysis. For this purpose, the R&S NRP-Z81 from Rohde & Schwarz is a solution that meets all requirements. Featuring a sampling rate of 80 million values per second and a video bandwidth of 30 MHz, the R&S NRP-Z81 also provides highly accurate measurements of the envelope of HSPA and UMTS LTE signals. The high dynamic range of up to 70 dB for peak power measurements makes it possible to display signal details up to -50 dBm. At the same time, the low zero drift of <1 nW ensures a high repeatability of the measurements. The average power can be measured in a range from -60 dBm to +20 dBm, no matter whether the signal is modulated or unmodulated. The R&S NRP-Z81 sensor can be directly operated via a PC or in combination with the R&S NRP base unit. The operation of the base unit is consistently adapted to the new sensor. The revised trace mode allows you to graphically display the signal as a trace. Common oscilloscope operating elements are used to configure the display and select the measurement function. Since the instrument provides a user-scalable display, even the smallest details can be analyzed. The marker functions of the R&S NRP allow you to easily determine time distances, rise and fall times as well as minima and maxima. In addition, the R&S NRP-Z81 makes it possible to determine the amplitude statistics of a signal. At maximum video bandwidth, the instrument handles measurement and complete evaluation of the distribution function (e.g. CCDF) with one million sampled values in 12.5 ns. By defining gates or timeslots, you can perform power measurement and statistical analysis in signal synchronous measurement windows.