Field notes from European Microwave Week 2026, London.
Two of Keysight's EuMW 2026 stations dealt with what happens outside the lab. One was about watching the radio spectrum with networked receivers. The other was about checking that a positioning receiver tells the truth. Both demos are simple on screen, and both come down to the same engineering question: how do you know that your view of the RF environment is correct?
Spectrum monitoring: a receiver is only as good as its settings
The monitoring software was connected over Ethernet to a remote receiver named "EuMW 17D", with an option to push settings to all receivers on the network at once. The settings read:
- centre frequency 750 MHz, bandwidth 100 MHz;
- attenuation 0 dB, preamp off;
- 401 frequency points.
A marker sat near 706 MHz at roughly −81 dBm, with a few narrow carriers and a raised band of activity towards the upper end of the span.
Three settings on that panel decide what a monitoring network can and cannot see:
- Resolution: 401 points across 100 MHz means one point every 250 kHz. A narrowband emitter falling between points shows up attenuated or not at all. For detecting short or narrow signals, point density, RBW and dwell time matter more than the span.
- Attenuation and preamp: 0 dB attenuation with the preamp off is a middle setting. A strong nearby transmitter, common at a trade show and even more so near a cell site, can push the receiver front end into compression and create intermodulation products that look like real emitters. Before reporting an "unknown signal", change the attenuation and check that it does not move.
- Synchronisation: pushing identical settings to every receiver is what makes their results comparable. It is also the basis for locating an emitter, for example by time difference of arrival, which needs time-aligned captures.
Next to the monitor, several handheld analysers with antennas were showing their own spectrum displays. A distributed network does not replace those. It decides where to send them.
PNT verification: test the receiver against a known truth
Under the banner "Verify PNT Performance" (positioning, navigation and timing), a standard GNSS evaluation tool was connected to a u-blox M8-series receiver. The display showed:
- a clean circular horizontal track;
- a sky plot full of satellites;
- a heading of 263.92° and a speed of 4.74 m/s (17.1 km/h).
A receiver standing on a booth table does not drive in circles at 17 km/h, so the signals were presumably coming from a GNSS simulator replaying a defined trajectory. A second screen showed a scenario editor with a map of southern England.
This is the key idea of PNT verification. With live sky signals you never know the true position precisely, so you cannot measure the error. With a simulator you define the truth, the trajectory, and the receiver's output can be compared against it point by point. The circular test pattern is useful because any lag, overshoot or bias shows up as a distorted or shifted circle.
The same approach extends to the scenarios that matter for resilience:
- jamming, with controlled interference at defined power levels;
- spoofing, with false signals that pull the solution away;
- multipath and obscuration;
- multi-constellation behaviour as satellites are removed.
Each needs a known truth to score against, and a simulator is the practical way to provide it.
Takeaway
Spectrum monitoring and PNT testing look like different topics, but they share one discipline: know the limits of your own measurement before you trust what it reports. For a monitoring receiver, that means resolution, linearity and synchronisation. For a positioning receiver, it means comparing its output against a trajectory you defined yourself. Both demos were quiet screens, and both were about how to avoid being misled by the RF environment.
Notes: Observations and interpretations are my own, based on what was running at the booth during the show. Screen values are as read from my photos. The receiver hardware behind the monitoring software, the GNSS simulator model and the scenario details were not confirmed with the exhibitor.