3 ms·

Active Electronically Scanned Array (AESA) Antenna

peter_d_sherman 6y ago
https://www.slashgear.com/elon-musk-shares-starlink-expansion-roadmap-spacex-readies-more-beta-invites-03645614/ https://www.slashgear.com/elon-musk-shares-starlink-expansio... >"Comments: schmoe • 5 months ago Not explained in the article: The reason why the user terminal [Starlink Dish] is so expensive is because that "dish" is actually an Active Electronically-Scanned Array (AESA) flat-panel antenna. It has over 1,000 individual radio transmitter/receivers which work together as a phased-array. It's a lot more complex than a traditional parabolic dish antenna with just 1 transmitter and 1 receiver for use with traditional geosynchronous communications satellites." Related: Starlink (https://en.wikipedia.org/wiki/Starlink https://en.wikipedia.org/wiki/Starlink) From Main Article (https://en.wikipedia.org/wiki/Active_electronically_scanned_array https://en.wikipedia.org/wiki/Active_electronically_scanned_...): >"An active electronically scanned array (AESA) is a type of phased array antenna, which is a computer-controlled array antenna in which the beam of radio waves can be electronically steered to point in different directions without moving the antenna. In the AESA, each antenna element is connected to a small solid-state transmit/receive module (TRM) under the control of a computer, which performs the functions of a transmitter and/or receiver for the antenna. This contrasts with a passive electronically scanned array (PESA), in which all the antenna elements are connected to a single transmitter and/or receiver through phase shifters under the control of the computer. AESA's main use is in radar, and these are known as active phased array radar (APAR). The AESA is a more advanced, sophisticated, second-generation of the original PESA phased array technology. PESAs can only emit a single beam of radio waves at a single frequency at a time. The PESA must utilize a Butler matrix (https://en.wikipedia.org/wiki/Butler_matrix https://en.wikipedia.org/wiki/Butler_matrix) if multiple beams are required. The AESA can radiate multiple beams of radio waves at multiple frequencies simultaneously." [...] >"The transmitter elements were typically klystron tubes or magnetrons, which are suitable for amplifying or generating a narrow range of frequencies to high power levels." [...] >"In 2007, tests by Northrop Grumman, Lockheed Martin, and L-3 Communications enabled the AESA system of a Raptor to act like a WiFi access point, able to transmit data at 548 megabits per second and receive at gigabit speed; this is far faster than the Link 16 system used by US and allied aircraft, which transfers data at just over 1 Mbit/s.[12]" PDS: And you thought your Starlink Dish -- was just a plain old satellite dish!

https://www.slashgear.com/elon-musk-shares-starlink-expansion-roadmap-spacex-readies-more-beta-invites-03645614/ https://www.slashgear.com/elon-musk-shares-starlink-expansio... >"Comments: schmoe • 5 months ago Not explained in the article: The reason why the user terminal [Starlink Dish] is so expensive is because that "dish" is actually an Active Electronically-Scanned Array (AESA) flat-panel antenna. It has over 1,000 individual radio transmitter/receivers which work together as a phased-array. It's a lot more complex than a traditional parabolic dish antenna with just 1 transmitter and 1 receiver for use with traditional geosynchronous communications satellites." Related: Starlink (https://en.wikipedia.org/wiki/Starlink https://en.wikipedia.org/wiki/Starlink) From Main Article (https://en.wikipedia.org/wiki/Active_electronically_scanned_array https://en.wikipedia.org/wiki/Active_electronically_scanned_...): >"An active electronically scanned array (AESA) is a type of phased array antenna, which is a computer-controlled array antenna in which the beam of radio waves can be electronically steered to point in different directions without moving the antenna. In the AESA, each antenna element is connected to a small solid-state transmit/receive module (TRM) under the control of a computer, which performs the functions of a transmitter and/or receiver for the antenna. This contrasts with a passive electronically scanned array (PESA), in which all the antenna elements are connected to a single transmitter and/or receiver through phase shifters under the control of the computer. AESA's main use is in radar, and these are known as active phased array radar (APAR). The AESA is a more advanced, sophisticated, second-generation of the original PESA phased array technology. PESAs can only emit a single beam of radio waves at a single frequency at a time. The PESA must utilize a Butler matrix (https://en.wikipedia.org/wiki/Butler_matrix https://en.wikipedia.org/wiki/Butler_matrix) if multiple beams are required. The AESA can radiate multiple beams of radio waves at multiple frequencies simultaneously." [...] >"The transmitter elements were typically klystron tubes or magnetrons, which are suitable for amplifying or generating a narrow range of frequencies to high power levels." [...] >"In 2007, tests by Northrop Grumman, Lockheed Martin, and L-3 Communications enabled the AESA system of a Raptor to act like a WiFi access point, able to transmit data at 548 megabits per second and receive at gigabit speed; this is far faster than the Link 16 system used by US and allied aircraft, which transfers data at just over 1 Mbit/s.[12]" PDS: And you thought your Starlink Dish -- was just a plain old satellite dish!