Use of the K u-band for satellite communications in tropical regions like Indonesia is becoming more frequent. This model can create a 99.7% available link so that K u-band can be applied in Indonesia. The DAH model has become an ITU recommendation since 2001 (Recommendation No. The DAH Model for rain attenuation prediction is valid for Indonesia, as is the ITU model. Measurements of rain attenuation in Indonesia have been done for satellite communication links in Padang, Cibinong, Surabaya and Bandung. Higher power can overcome the loss to rain fade. This problem can be solved by using an appropriate link budget when designing the wireless communication link. Using frequencies higher than 10 GHz in a heavy rain area usually gives poor results. This statement has made many people unsure about using K u-band (11 – 18 GHz) in Indonesia. The ITU has categorized Indonesia as Region P, countries with very high rain precipitation.
TRANSMIT BAND LICENSE
The 11.7 to 12.5 GHz segment is allocated to the BSS ( broadcasting satellite service).Īustralia is part of ITU Region 3 and the Australian regulatory environment provides a class license that covers downlinking from 11.70 GHz to 12.75 GHz and uplinking from 14.0 GHz to 14.5 GHz. In Europe K u band is used from 10.7 to 12.75 GHz (LOF Low 9.750 GHz, LOF High 10.600 GHz) for direct broadcast satellite services such as those carried by the Astra satellites. Segments in those regions are represented by ITU Region 1, and they are the 11.45 to 11.7 and 12.5 to 12.75 GHz bands are allocated to the FSS ( fixed satellite service, uplink 14.0 to 14.5 GHz). BSS (DBS direct broadcast satellites) normally carry 16 to 32 transponders of 27 MHz bandwidth running at 100 to 240 watts of power, allowing the use of receiver antennas as small as 18 inches (450 mm). The 12.2 to 12.7 GHz (LOF 11.25 to 11.75 GHz) segment is allocated to the BSS ( broadcasting satellite service). There are more than 22 FSS K u band satellites orbiting over North America, each carrying 12 to 48 transponders, 20 to 120 watts per transponder, and requiring a 0.8-m to 1.5-m antenna for clear reception. Segments in most of North and South America are represented by ITU Region 2 from 11.7 to 12.2 GHz ( Local Oscillator Frequency (LOF) 10.75 to 11.25 GHz), allocated to the FSS ( fixed satellite service), uplink from 14.0 to 14.5 GHz. A satellite dish on a residence, which receives satellite television channels over a K u band microwave beam from a broadcast communications satellite in a geostationary orbit 35,700 kilometres (22,000 miles) above the Earth.
One use of the band is direct-broadcast satellite television. Some frequencies in this radio band are employed in radar guns used by law enforcement to detect vehicles speeding, especially in Europe. NBC was the first television network to uplink a majority of its affiliate feeds via K u band in 1983. The band is split by the International Telecommunication Union (ITU) into multiple segments that vary by geographical region. K u band satellites are also used for backhauls and particularly for satellite from remote locations back to a television network's studio for editing and broadcasting. K u band is primarily used for satellite communications, most notably the downlink used by direct broadcast satellites to broadcast satellite television, and for specific applications such as NASA's Tracking Data Relay Satellite used for International Space Station (ISS) communications and SpaceX Starlink satellites. In radar applications, it ranges from 12 to 18 GHz according to the formal definition of radar frequency band nomenclature in IEEE Standard 521-2002. The symbol is short for "K-under" (originally German: Kurz-unten), because it is the lower part of the original NATO K band, which was split into three bands (K u, K, and K a) because of the presence of the atmospheric water vapor resonance peak at 22.24 GHz, (1.35 cm) which made the center unusable for long range transmission. The K u band ( / ˌ k eɪ ˈ j uː/) is the portion of the electromagnetic spectrum in the microwave range of frequencies from 12 to 18 gigahertz (GHz).
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