DISCLAIMER: The sample surveys displayed below are for educational purposes only and do not necessarily reflect the (historic) situation in a market.

This case brings us to Belgium, which was one of the first countries to launch 5G NR in the 2100 MHz band. The incumbent operator Proximus (Belgacom) refarmed their 2100 MHz spectrum to be used for 3G and 5G NR. By chance, the local operator Base (Telenet) emits a 4G signal adjacent to the Proximus allocation. As a result we can measure a 3G HSPA, 5G NR and 4G LTE signal next to each other. The 5G NR signal thus being sandwitched between the 3G and 4G signal. One could wonder why the 5G NR carrier is not positioned at the edge of the 2100 MHz band instead. At the time of the spectrum scan, the Proximus 5G network operated in NSA Non-Stand-Alone mode and used the 1800 MHz band as anchor.

In Mexico, we found an interesting case of 4G LTE carrier deployment in the 2.6 GHz band.

On 15 July 2011 two broadcast towers in the Netherlands caught fire on the same day. The Lopik tower (367 meters) survived the fire, but the Smilde tower (294 meters) collapsed. Terrestrial Radio and TV broadcasts were interrupted in large parts of the country for about 1 year. A temporary mast (100 meters) was erected in nearby Assen city to repair some of the lost coverage. The sequence of events on the day of the Smilde collapse is clearly visible in the spectrograms. The Smilde tower has been rebuild. Despite strong rumors, the cause of the fires has not been determined to date.

Photo: Stills from TV Drenthe News Broadcast, 15 July 2011.

While the migration from terrestrial Analogue TV (PAL/SECAM/NTSC) to Digital TV (DVB/ISDB/ATSC) runs very smooth, there is no concensus about the future of Analogue Sound Broadcasting (FM/AM). The USA currently favours an In-Band-On-Channel IBOC solution and two proprietary solutions can be found on air. The top left plot shows the HD Radio solution by iBiquity Digital Corporation. The recording was made in San Francisco (94.9 MHz / 30kW ERP / 357m HAAT). The HD Radio OFDM carriers are placed on either side of the analogue FM-carrier at ±130-200kHz distance.

The neighbouring station at 95.7 MHz also has enabled HD Radio. The top right plot shows the analogue baseband (MPX) signal after demodulation which is not affected by the HD Radio technology. The 2nd proprietary IBOC solution is FMeXtra by Digital Radio Express and is shown in the bottom two plots. The signal was also captured in San Francisco (88.5 MHz / 110kW ERP / 387m HAAT). The FMeXtra technology places the OFDM carriers in the baseband (SCA), thus before FM modulation. Digital Radio Express claims that the modulation power will increase only little due to FMeXtra.