This battery-powered spectrum analyzer provides full-sized functionality from 100 kHz to 4 GHz for testing and commissioning base stations and broadcast facilities.
Portable, handheld spectrum analyzers such as the new model 9102 from Boonton Electronics allow engineers to bring their measurement gear to a site, rather than the other way around. This battery-powered test tool is a mere 355 X 190 X 91 mm but packs all the measurement power of a rack-mount spectrum analyzer. It covers a frequency range from 100 kHz to 4 GHz and features a built-in frequency counter for accurately identifying received signals with 1-Hz frequency resolution.
The handheld model 9102 spectrum analyzer (see figure) tunes across a selected span from 10 kHz to 4 GHz (full scan) with 1-kHz tuning resolution. It can also perform zero-span (0 Hz) measurements for evaluating modulated signals. The instrument includes a wide range of resolution-bandwidth filters, from 100 Hz to 1 MHz; these can be set manually or automatically selected by the 9102 based on other measurement parameters. Similarly, video-bandwidth filters can be selected manually or automatically from 10 Hz to 1 MHz. Frequency sweep times can be set from 1 ms to 250 s. The aforementioned frequency counter works on signal levels as low as -90 dBm. The counter can be set for different frequency resolution levels of 1 Hz, 10 Hz, and 100 Hz.
The 9102 exhibits a displayed average noise level (DANL) of typically -130 dBm from 10 MHz to 1 GHz and typically -135 dBm from 1 to 4 GHz. The reference level can be set from -100 to +30 dBm with 0.1-dB resolution. The analyzer's dynamic measurement range is defined by the maximum measurable input level, which is +20 dBm, and the DANL. (The 9102 actually handles input levels to +30 dBm without damage.) The dynamic display range (how much can be shown on the screen at one time) is 70 dB. To assist in measuring high-level signals, the 9102 is equipped with as much as 50-dB input attenuation, which can be added in 10-dB steps. With the attenuator set to 10 dB, the spectrum analyzer shows a quite respectable level accuracy of ±1 dB from 10 MHz to 3.6 GHz.
The portable analyzer shows test results on a 6.5-in. color VGA thin-film-transistor (TFT) display screen with 640 X 480-pixel resolution. The microprocessor-powered instrument is assisted by a field-programmable gate array (FPGA), which handles digital-signal-processing (DSP) chores on captured signals. It performs a number of more complicated measurements with the push of a button, including channel power, adjacent-channel power ratio (ACPR), and occupied-bandwidth (OBW) measurements. The analyzer is armed with a full complement of detectors, including positive/negative, peak, positive peak, negative peak, and sample detectors, for performing electromagnetic-interference (EMI) measurements. An optional root-mean-square (RMS) detector supports measurements on digitally modulated signals. The 9102 allows operators to set as many as six measurement markers, as many as 99 limit templates, and pass/fail limit lines.
Another option equips the 9201 with a 1-MHz-to-4-GHz tracking generator for reflection and distance-to-fault measurements. The tracking generator can be adjusted from -30 to -10 dBm for performing measurements on both active and passive components.
The 9201 weighs just 7 lbs. (3.2 kg) with its rechargeable battery and the optional tracking generator. It includes a headphone jack, an RJ-45 local-area-network (LAN) connector, and a serial interface.