How to measure LTE level with any RANGERNeo field strength meter
All PROMAX field strength meters can be used to evaluate and eliminate LTE interferences on television reception.
Our analysers have a 7" display (about 18 cm) that shows on screen spectrum, measures and decoded image at the same time. The ultra fast spectrum analyser includes professional features such as MAX Hold, MIN Hold, markers on trace, storage data, measures comparison and high precision in the trace of the spectrum.
All PROMAX HD RANGER field strength meters can be used to reduce LTE interferences
In addition to other tools such as echoes, constellation, attenuation test and task planner, PROMAX keeps releasing new tools for its meters. In this article we will focus on measuring level and power for the LTE signal.
Select the bandwidth for the LTE signal
First go to the F2 function key and then select GENERIC in the Signal type menu.
Figure 1: Select the GENERIC signal type
Once selected the GENERIC signal type, the field strength meter allows you to adjust the bandwidth for the LTE signal. Typically the bandwidth is 10 MHz, so user can measure each operator in both downlink and uplink.
However sometimes operators share its spectrum with other operators. In this case we must choose the appropriate bandwidth, 5 MHz.
Figure 2: Choose the bandwidth
The meter will alert us that these conditions are not acceptable to demodulate this signal.
Work in FREQUENCY mode (not in CHANNEL mode)
As an example, the LTE frequency band for digital dividend in Spain it is as follows:
|A||ORANGE||From 791 to 801 MHz||From 832 to 842MHz|
|B||VODAFONE||From 801 to 811 MHz||From 842 to 852MHz|
|C||TELEFONICA||From 811 to 821 MHz||From 852 to 862MHz|
Therefore, we must set the center frequency for each link and each operator. For example, 796 MHz is the center frequency for Orange downlink.
Figure 3: Work in FREQUENCY mode and adjust the Span.
Finally, we measure. In Figure 4 we can see the signal level (85.3 dBµV) with bandwidth at 10 MHz and the proper center frequency. This signal has been captured in Madrid.
The maximum power that can emit a base station by Spanish law is 63 dBm. The following link shows a table of equivalences between these two measurements units:
Figure 4: LTE signal level in dBµV
The PROMAX field strength meters can receive notifications about new features and also about firmware updates to improve its performance. For example, this power measurement for LTE is added to the LTE Ingress Test already available. This LTE Ingress test measures the signal level with and without filter. In Figure 5, you can see how an external cavity filter can reduce the LTE signal from 86.55 to 54.55 dBµV.
Figure 5: LTE Ingress test
PROMAX is a leading manufacturer of test and measurement systems, broadcast and TV signal distribution equipment. Our product lines include measuring instruments for cable TV, satellite TV, broadcast, wireless and fibre optics networks, FTTH and GPON analyzers. DVB-T modulators, IP streamers or IP converters (ASI, DVB-T) are among the company’s latest developments.