N9092EM0E Avionics X-Series Measurement Application

 N9092EM0E Features

Analyzes and verifies the quality of signals used in testing basic aircraft navigation and instrument landing Provides exceptional accuracy for VOR bearing analysis

Offers ILS measurements for both Localizer and Glideslope with high DDM accuracy

Supports Marker Beacon and ADF measurements

Capable of analyzing RF and baseband¹ input signals

Fully specified on the N9030B PXA with multi-touch user interface

Avionics Measurements

Keysight N9092EM0E Avionics Measurement application software, installed in the N9030B PXA high-performance signal analyzer, enables aviation customers to analyze and qualify air navigation and landing signals; specifically, VOR (VHF Omnidirectional Range), ILS (Instrument Landing System), Marker Beacon, and ADF (Automatic Direction Finder) measurements.

X-Series measurement applications

X-Series measurement applications increase the capability and functionality of Keysight Technologies, Inc. signal analyzers to speed time to insight. They provide essential measurements for specific tasks in general-purpose, cellular communications, wireless connectivity applications, covering established standards or modulation types.

X-Series measurement applications can help you:

Gain more insight into device performance with intuitive display and graphs for your application. Select from our library of over 25 different measurement applications

Choose the license structure that meets your business needs. We provide a range of license types (node-locked, transportable, floating or USB portable) and license terms (perpetual or time-based).

VOR measurements

A ground-based VOR transmitter emits two signals: a Reference signal broadcast evenly in all directions, and a Variable component on a directional beam which is rotating (as a lighthouse) around 360 deg of the compass. Both use the same RF carrier frequency, and combine in the aircraft’s antenna/receiver during flight. The aircraft’s receiver compares the two components, and determines the aircraft’s azimuth (compass bearing) along a “radial” vector centered at the airport (e.g. “bearing” of 70 deg, relative to north, centered at airport). The system can be used in multiple ways, but pilots commonly use VOR to set up an ‘approach’ lined up with the runway.

However, aircraft receivers are usually tested on the ground, using a signal generator which emits both Reference and Variable signals (on the same cable or antenna) that artificially represents a radial bearing (as if the aircraft was in flight). The N9092EM0E verifies that such signal generators are accurate.

VORs are assigned radio channels between 108.0 MHz and 117.95 MHz (with 50 kHz spacing); this is in the very high frequency (VHF) range. The N9092EM0E measures the frequency and power of this RF carrier with high accuracy.

“VOR Bearing” is the key test parameter for VOR systems. The N9092EM0E measures Bearing with the accuracy specification of +/- 0.025 deg, giving users high confidence for their VOR transmitting signal’s correctness. Additionally, the modulating frequencies, AM depth, and FM deviation of the subcarrier tones can also be simultaneously measured. Figure 1 shows a quad-view display of VOR measurement results by the N9092EM0E Avionics app, with graphical displays. Figure 2 shows the Results-only display, with numerical results for all important VOR parameters.

ILS measurements

A ground-based ILS system emits 4 directional beams arranged around the ideal flight path leading to the runway. One pair of beams, called “Localizer” (LOC), form a left/right pair. The left beam is modulated at 90 Hz, and the right at 150 Hz; however, both are on the same RF carrier frequency. They combine in the aircraft’s antenna/receiver, and the relative strength on the two beams tells the pilot if the plane is left or right from ideal. Likewise, another pairs of beams, called “Glideslope” (GS), form an up/down pair, and tell the pilot if the plane is coming in high or low vs ideal.

Since aircraft receivers are usually tested on the ground, an ILS signal generator emits both 90-Hz and 150-Hz modulated signals (on the same cable or antenna), and artificially simulates the signal that would be seen by an aircraft that was left/right or high/low in its approach. The N9092EM0E verifies that such signal generators are accurate.

The radio transmitter of the LOC uses the RF signal at frequency between 108.1 MHz 119.95 MHz, while GS works at frequencies between 329.15 MHz and 335.0 MHz. The difference in depth of modulation (DDM) of these 2 base tones can be translated into the deviations from the ideal landing path. Therefore, the DDM is one of the most critical parameter in the ILS and the accuracy of the DDM measurements is paramount.

The N9092EM0E Avionics application automatically set up the measurement conditions per the avionics standards. Figure 3 shows the quad view of the ILS LOC measurement results including DDM, SDM (sum of depth of modulation), frequency of the base tones and their corresponding AM depth, along with the RF frequency, RF power level, and the spectra of RF and basebands, respectively. The industry-leading DDM accuracy of +/-0.0001 offers ultimate userconfidence for their ILS testing.