Ku band

IEEE Ku band
Frequency range
12–18 GHz
Wavelength range
2.5–1.67 cm
Related bands

The Ku band (/) is the portion of the electromagnetic spectrum in the microwave range of frequencies from 12 to 18 gigahertz (GHz). 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 (Ku, K, and Ka) 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. In radar applications, it ranges from 12-18 GHz according to the formal definition of radar frequency band nomenclature in IEEE Standard 521-2002.[1][2]

Ku 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 both space shuttle and International Space Station (ISS) communications. Ku 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. The band is split by the International Telecommunication Union (ITU) into multiple segments that vary by geographical region. NBC was the first television network to uplink a majority of its affiliate feeds via Ku band in 1983.

Some frequencies in this radio band are employed in radar guns used by law enforcement to detect vehicles speeding, especially in Europe.[3]

Segments and regions

One use of the band is direct-broadcast satellite television. A satellite dish on a residence, which receives satellite television channels over a Ku band microwave beam from a broadcast communications satellite in a geostationary orbit 35,700 kilometres (22,000 miles) above the Earth.

The Americas

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. There are more than 22 FSS Ku 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.

The 12.2 to 12.7 GHz (LOF 11.25 to 11.75 GHz) segment is allocated to the BSS (broadcasting satellite service). 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).

Europe and Africa

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). In Europe Ku band is used from 10.7 to 12.75 GHz (LOF Low 9.750 GHz, LOF High 10.750 GHz) for direct broadcast satellite services such as those carried by the Astra satellites. The 11.7 to 12.5 GHz segment is allocated to the BSS (broadcasting satellite service).

Australia

Australia 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.[4]

Indonesia

The ITU has categorized Indonesia as Region P, countries with very high rain precipitation. This statement has made many people unsure about using Ku-band (11 – 18 GHz) in Indonesia. If frequencies higher than 10 GHz are used in a heavy rain area, a decrease in communication availability results. This problem can be solved by using an appropriate link budget when designing the wireless communication link. Higher power can overcome the loss to rain fade.

Measurements of rain attenuation in Indonesia have been done for satellite communication links in Padang, Cibinong, Surabaya and Bandung. The DAH Model for rain attenuation prediction is valid for Indonesia, in addition to the ITU model. The DAH model has become an ITU recommendation since 2001 (Recommendation No. ITU-R P.618-7). This model can create a 99.7% available link so that Ku-band can be applied in Indonesia.

The use of the Ku-band for satellite communications in tropical regions like Indonesia is becoming more frequent. Several satellites above Indonesia have Ku-band transponders, and even Ka band transponders. Newskies (NSS 6), launched in December 2002 and positioned at 95° East, contains only Ku-band transponders with a footprint on Indonesia (Sumatra, Java, Borneo, Celebes, Bali, Nusa Tenggara, Moluccas). NSS 6 is intended to be replaced by SES-12 at the same location, which launched in June 2018 and carries 54 Ku-band transponders. The iPSTAR satellite, launched in 2004 also uses Ku band footprints. Other satellites that provides Ku band covers Indonesia are Palapa D, MEASAT 3/3A, JCSAT-4B, AsiaSat 5, ST 2, Chinasat 11, Korea Telecom Koreasat 8/ABS 2 (2nd half 2013), and SES-8.

Others

Other ITU allocations have been made within the Ku band to the fixed service (microwave towers), radio astronomy service, space research service, mobile service, mobile satellite service, radiolocation service (radar), amateur radio service, and radionavigation. However, not all of these services are actually operating in this band and others are only minor users.

Other Languages
català: Banda Ku
eesti: Ku-riba
español: Banda Ku
euskara: Ku banda
français: Bande Ku
한국어: Ku 밴드
Bahasa Indonesia: Pita frekuensi Ku
italiano: Banda Ku
עברית: Ku-band
Bahasa Melayu: Jalur Ku
polski: Pasmo Ku
português: Banda Ku
русский: Ku-диапазон
українська: Ku-діапазон
Tiếng Việt: Băng tần Ku
中文: Ku波段