![]() ![]() In the case of apartments, hotels, schools, colleges, offices, etc. in the direction which the TV antenna points, and considerably closer than the TV transmitter which it is desired to receive resulting in a high level of interfering signal in the TV system. Although the base stations may be relatively far away from the TV equipment they may be adjacent to the TV antenna, or if further away they may be in the 'beam' of the TV antenna, i.e. All signals passing through the overloaded device will be affected for as long as the device remains overloaded.Įssentially there are two types of interference sources in the 800 MHz band: The LTE base stations and the mobile terminals - handsets, tablets, dongles - which are sometimes close to TV equipment. Overload in the RF chain will not only affect one TV channel. In severe cases of interference the error correction will not cope at all and this will result in a black TV-screen and / or complete loss of sound.If the interference is sufficiently severe such that FEC cannot correct all of the errors, there will be pixelation in the picture and/or there will be sound drop-outs. ![]() When forward error correction (FEC) is adequate, the TV reception will be unaffected.flat panels, set top boxes, USB-tuners and digital video recorders.ĭepending on the dynamic range performance of the affected receiving equipment, the following may happen: ![]() Strong LTE base station signals in 800 MHz band, may cause limiting or clipping, that is due to overdrive in antenna amplifiers and/or DTT tuners in e.g. Due to the very limited guard band between the new services and the existing TV services in some cases the LTE 800 base station signals may cause interference to DTT particularly in EU channels 59 and 60. Most TV receiving equipment in current use and currently on the market was not designed with the expectation that there would be anything but TV signals in the frequency range 470 MHz to 862 MHz. The reason for the interference problem is that the RF chain in TV-equipment is designed to receive 470–862 MHz (EU channels 21–69) and therefore includes the range of frequencies which the new services are, or will be, using. Some claim that there have not been enough interference studies made in the EU. įrom the year 2013 the 800 MHz band can be used to deliver wireless broadband services, in Europe. The European Parliament approved in May 2010, and Japan in 2012, the change of use of the 800 MHz band making it available for purposes other than broadcasting (television) – e.g. In most territories the band was also used by Services Ancillary to Broadcasting (SAB) or Services Ancillary to Programme Making (SAP), both often now referred to as PMSE (Programme Making and Special Events) in the form of professional wireless microphones, radio talkback systems and wireless monitor systems. In Europe and to some extent elsewhere, the band corresponds to UHF channel 61–69. As such it is also referred to as " digital dividend" spectrum. ![]() 470 MHz to 862 MHz) it was allocated by the ITU to Broadcasting as the primary user in Region 1 and was used for analogue television broadcasting before changing to digital terrestrial television in many countries. The 800 MHz frequency band is a portion of the electromagnetic spectrum, or frequency band, that encompasses 790–862 MHz.īeing a part of the spectrum known as "UHF Bands IV and V" (i.e. ![]()
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