RFScan Analyzer

Analyze RFScan captures directly in your browser

RFScan Analyzer opens the capture files produced by an RF scan on a base station radio module — an RFMonitoring archive or a bare .rfcap file — and turns the raw I/Q samples inside into the uplink spectrum. It reads the container, decodes the samples, computes the FFT and draws the traces, all in the page you are reading. There is no installation, no account, and no server involved at any point.

It is built for the moment on a site visit when you have a set of captures, a suspicion about one antenna, and no RF test equipment within reach. Load the whole set at once and every antenna gets its own screen on a shared dB scale, so a lifted noise floor on one path is visible before you have read a single number.

Supported analysis

• Spectrum analysis — the uplink spectrum computed from the captured I/Q samples.
• FFT — selectable size from 256 to 8192 points, with Hann, Blackman–Harris, Hamming or rectangular windowing.
• Average / Min Hold / Max Hold — Welch-averaged trace with the per-segment minimum and maximum around it.
• Waterfall — time against frequency, in absolute level or as change against the capture's own average.
• Antenna comparison — every capture of a set on one dB scale, plus a noise-floor table ranked against the quietest antenna.
• RF peak detection — each peak measured against the local noise floor beside it, with peaks outside the carrier flagged.
• Intermodulation analysis — products of the downlink carriers named in the loaded captures, to 3rd, 5th or 7th order, matched against what was actually received.
• Before / After comparison — captures matched by sector, antenna and band, with the noise change and a verdict per pair.
• CSV export — the active trace as plain comma-separated values.
• Printable PDF reports — an analysis report or a before/after report, rendered for print.

How it works

1. Export the RFScan from the BTS environment.
2. Open the RFScan or RFCAP file.
3. Select the antenna/capture.
4. Inspect the spectrum.
5. Compare antennas or captures.
6. Export the analysis if required.

How to open Nokia RFScan and RFCAP files

Nokia RFScan captures are commonly exported as RFMonitoring archives containing one or more RFCAP files. RFScan Analyzer lets you open compatible Nokia RFScan and RFCAP captures directly in the browser without installing RF Monitor or MATLAB Runtime.

Open the RFMonitoring ZIP archive or a bare RFCAP file, then inspect the uplink spectrum, waterfall, noise floor, detected peaks and antenna-to-antenna differences. Multiple captures can be loaded together to compare sectors or antenna paths.

The capture is processed locally on your computer. RFScan Analyzer does not upload the RFScan, filename, cell information or radio-module metadata to a server.

Privacy

Your RFScan files stay on your device. When you open a capture, the browser reads it from your disk into the memory of this tab. The archive is inflated, the samples decoded and the spectrum computed by JavaScript running on your machine. Nothing is transmitted.

The page sends no file, no filename, no metadata, no cell ID, no serial number and no measurement — not to this site, not to anyone. There is no upload in the tool and no backend to receive one.

Nothing is stored either. Close the tab and the captures are gone from the browser; the files on your disk are never modified.

For completeness: like the rest of GSM Field Suite, this page can count visits with Google Analytics, and only after you accept the consent banner. Those counts record that the page was opened and that a capture was opened, successfully or not — a plain event name and nothing more. Nothing read from your capture is ever included. The page's Content-Security-Policy permits no outbound destination other than Google Analytics, so no other network request is possible.

A note on levels and calibration

Levels are shown as estimates. The capture carries raw sample values and no calibration constant, so converting them to dBm requires an offset. RFScan Analyzer applies a user-defined calibration offset, adjustable in the advanced settings, with a default chosen to line captures up with the levels printed in a typical RF scan report.

Absolute RF power depends on capture calibration and hardware configuration. Treat the displayed dBm figures as estimates for comparison, not as certified absolute measurements. The comparisons between antennas of the same set — the “over the quietest” column in particular — need no calibration at all and are the figures to rely on.

FAQ

What is an RFCAP file?

An RFCAP file is the raw capture produced by an RF scan on a base station radio module. It holds blocks of I/Q samples together with a header describing the centre frequency, sample rate, band plan and module. RFScan Analyzer reads those samples and computes the spectrum from them, rather than displaying a pre-rendered picture.

Can I open Nokia RFScan files without RF Monitor?

RFScan Analyzer provides an independent browser-based method for analyzing compatible RFScan/RFCAP captures. It is not a replacement for any vendor tool and contains no part of one.

Are my RFScan files uploaded?

No. Processing is performed locally in your browser.

Does RFScan Analyzer require MATLAB?

No. It runs in the browser and needs no MATLAB, no runtime and no installation.

Is this an official Nokia tool?

No. RFScan Analyzer is independently developed.

Which browsers are supported?

Current versions of Chrome, Edge and Firefox. Inflating an archive uses the browser's built-in DecompressionStream; on a browser without it, unzip the archive yourself and open the .rfcap directly.

Is there a file size limit?

Yes, for your own protection: captures up to 200 MB, archives of up to 500 entries expanding to no more than 500 MB in total. These sit far above any real RF scan and exist so that a malformed or hostile file cannot exhaust the browser.