AN/APQ-181

Light surface below wing edges is the AN/APQ-181 radar antenna

The AN/APQ-181 is an all-weather, low probability of intercept (LPI) phased array radar system designed by Hughes Aircraft (now Raytheon) for the U.S. Air Force B-2A Spirit bomber aircraft. The system was developed in the mid-1980s and entered service in 1993. The APQ-181 provides a number of precision targeting modes, and also supports terrain-following radar and terrain avoidance. The radar operates in the Ku band (a subset of the J band). The original design uses a TWT-based transmitter with a 2-dimensional passive electronically scanned array (PESA) antenna.

In 1991, the B-2 Industrial Team (including Hughes as a major subcontractor) was awarded the Collier Trophy in recognition of the "design, development, production, and flight testing of the B-2 aircraft, which has contributed significantly to America's enduring leadership in aerospace and the country's future national security."

In 2002, Raytheon was awarded a contract to develop a new, active electronically scanned array (AESA) version of the APQ-181. This upgrade will improve system reliability, and will also eliminate potential conflicts in frequency usage between the B-2 and commercial satellite systems that also use the J band.

In 2008 the Federal Communications Commission accidentally sold the APQ-181 frequency to a commercial user resulting in the need for installing new radar arrays at a cost of over $1 billion. All B-2 aircraft are expected to have the upgraded radar by 2010.[1]

See also

References

  1. ^ "Bandwidth Demands Crowd Military Needs". military.com. Archived from the original on March 26, 2009.

Read other articles:

Basilika Kunjungan Perawan Maria, Voćin

Basilika Kunjungan Perawan MariaBasilika Minor Kunjungan Perawan MariaKroasia: Crkva Pohođenja Blažene Djevice Marije u Voćinucode: hr is deprecated Basilika Kunjungan Perawan MariaLokasiVoćinNegara KroasiaDenominasiGereja Katolik RomaArsitekturStatusBasilika minorStatus fungsionalAktif Basilika Kunjungan Perawan Maria (Kroasia: Crkva Pohođenja Blažene Djevice Marije u Voćinucode: hr is deprecated ) adalah sebuah gereja basilika minor Katolik yang terletak di Voćin, Kroasia. Basi...

 

Hari Bendera (Australia)

Hari Bendera Nasional AustraliaDirayakan olehAustraliaJenisPatriotisme, Sejarah, NasionalismeMaknaUpacara pengibaran Bendera Australia pada tahun 1901KegiatanUpacara pengibaran benderaTanggal3 SeptemberFrekuensiTahunan Hari Bendera Nasional Australia telah dirayakan di Australia sejak 3 September 1996. Hari tersebut memperingati hari pada tahun 1901 di mana Bendera Nasional Australia pertama kali dikibarkan. Sejak tahun 2008, hari yang sama juga diperingati sebagai Hari Angkatan Laut Pedagang...

 

Alun-alun Tahrir

Koordinat: 30°02′40″N 31°14′09″E / 30.044422°N 31.235696°E / 30.044422; 31.235696 Alun-alun Tahrir. Menghadap utara melintasi gedung Mogamma dan patung Omar Makram di Alun-alun Tahrir. Alun-alun Tahrir (Arab: ميدان التحرير ; Midan al-Tahrircode: ar is deprecated , IPA: [meˈdæːn el-, ettæħˈɾiːɾ], Indonesia: Alun-Alun Kebebasancode: id is deprecated ) adalah sebuah alun-alun publik besar di pusat kota Kairo, Mesir. Alun-alun ...

1926 en sports équestres

Chronologies Chronologie du sport 1923 1924 1925  1926  1927 1928 1929Mois :Jan - Fév - Mar - Avr - Mai - Juin Juil - Aoû - Sep - Oct - Nov - Déc 1925 ◄◄ 1926 en sport ►► 1927 Chronologie dans le monde 1923 1924 1925  1926  1927 1928 1929Décennies :1890 1900 1910  1920  1930 1940 1950Siècles :XVIIIe XIXe  XXe  XXIe XXIIeMillénaires :-Ier Ier  IIe  IIIe Chronologies géographiques Afrique Afrique du Sud, Algé...

 

يوليا ميزا

يوليا ميزا (باللاتينية: Julia Maesa)‏  معلومات شخصية الميلاد 165حمص الوفاة 224روما مواطنة روما القديمة  الأولاد جوليا أفيتا ماميا[1][2]جوليا سؤامياس[3]  إخوة وأخوات جوليا دومنا[3]  اللغات اللاتينية  تعديل مصدري - تعديل   يوليا ميزا أو تنطق أيضا ب جوليا م...

 

保良局馬錦明夫人章馥仙中學

保良局馬錦明夫人章馥仙中學Po Leung Kuk Mrs.Ma-Cheung Fook Sien College翻漆後的校舍東北面（2022年3月）地址 香港新界離島區大嶼山東涌富東邨类型津貼中學宗教背景無隶属保良局创办日期1997年学区香港離島區東涌校長柯玉琼女士副校长鄭健華先生，劉俊偉先生助理校长梁煥儀女士职员人数56人年级中一至中六学生人数約700人，24個班別校訓愛、敬、勤、誠校歌保良局屬下校歌�...

Histoire de la construction

Johann Petrejus, illustration du Livre II du De Architectura de Vitruve, par Walther Hermann Ryff, 1547. Une définition de l'histoire de la construction, qui la distingue de l'histoire de l'architecture, pourrait nous être donnée par Vitruve : elle s'attache à décrire les matériaux que fournit la nature et l'usage qu'on en fait. Il n'y est pas question de l'origine de l'architecture, mais bien de celle des bâtiments, ainsi que de la manière dont on est parvenu à donner à l'art ...

 

Lauren Toyota

Canadian television personality Lauren ToyotaBornMississauga, Ontario, CanadaOccupationCookbook author, food bloggerAlma materDurham CollegeSubjectVegan cookbooksNotable works Hot for Food Vegan Comfort Classics: 101 Recipes to Feed Your Face (2018) Hot for Food All Day: Easy Recipes to Level Up Your Vegan Meals (2021) Websitewww.hotforfoodblog.com Lauren Toyota is a vegan cookbook author and creator of the blog, Hot for Food. She is a former Canadian television personality. Early life a...

 

2016年美國總統選舉

2016年美國總統選舉 ← 2012 2016年11月8日 2020 → 538個選舉人團席位獲勝需270票民意調查投票率55.7%[1][2] ▲ 0.8 %   获提名人 唐納·川普 希拉莉·克林頓 政党 共和黨 民主党 家鄉州 紐約州 紐約州 竞选搭档 迈克·彭斯 蒂姆·凱恩 选举人票 304[3][4][註 1] 227[5] 胜出州/省 30 + 緬-2 20 + DC 民選得票 62,984,828[6] 65,853,514[6]...

アプリケーションソフトウェア

「アプリケーション」はこの項目へ転送されています。英語の意味については「wikt:応用」、「wikt:application」をご覧ください。 この記事には複数の問題があります。改善やノートページでの議論にご協力ください。 出典がまったく示されていないか不十分です。内容に関する文献や情報源が必要です。（2018年4月） 古い情報を更新する必要があります。（2021年3月）出...

 

2020年普通高等学校招生全国统一考试

 若非特別註明，本條目所有時間皆為東八區標準時間（UTC+8）。 2020年7月7日上午8时17分，浙江省平阳县考区平阳县浙鳌高级中学考点大门口。可见防疫相关措施与设施。 7月7日上午的语文考试结束后，考生从北京101中学走出 7月7日上午11点33分，语文科目考试结束后等候在考点外的家长。摄于山东省东平县高级中学 2020年7月7日上午11时40分，语文科目考试结束后，考生走�...

 

Esophageal hiatus

Esophageal hiatusThe diaphragm. Under surface. (Esophageal hiatus labeled at center right.)DetailsIdentifiersLatinhiatus oesophageusTA98A04.4.02.011TA22344FMA58289Anatomical terminology[edit on Wikidata] In human anatomy, the esophageal hiatus is an opening in the diaphragm through which the esophagus and the vagus nerve pass. Structure The esophageal hiatus is an oval opening[1] in (sources differ) the right crus of the diaphragm[1]/left crus of the diaphragm, with fibres...

Panzer division (Wehrmacht)

German armored military unit of WWII This article has multiple issues. Please help improve it or discuss these issues on the talk page. (Learn how and when to remove these template messages) This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed.Find sources: Panzer division Wehrmacht – news · newspapers · books · scholar ·...

 

Operation Olive Branch

Turkish offensive against the SDF in Afrin Operation Olive BranchPart of the Rojava conflict, Turkish involvement in the Syrian Civil War, and the Kurdish–Turkish conflict (2015–present)  Turkish-backed opposition control  SDF control  Syrian Army controlFor a more detailed, up-to-date, interactive map, see here.DateMain combat phase:20 January[a] – 24 March 2018[9](2 months and 4 days)Main insurgency phase:[10][11][12&...

 

South Central Connecticut Planning Region, Connecticut

Planning region in ConnecticutSouth Central Connecticut Planning RegionPlanning regionSouth Central Regional Council of Governments (SCRCOG)From top left: New Haven Green, Main Street in Meriden, Downtown New Haven, Milford Harbor, Yale University campus LogoLocation within the U.S. state of ConnecticutConnecticut's location within the U.S.Coordinates: 41°22′N 72°49′W / 41.36°N 72.82°W / 41.36; -72.82Country United StatesState ConnecticutFounded2013L...

The Embarkation for Cythera

Painting by Antoine Watteau The Embarkation for Cythera (Louvre version): Many commentators note that it depicts a departure from the island of Cythera, the birthplace of Venus, thus symbolizing the temporary nature of human happiness. The Embarkation for Cythera (L'embarquement pour Cythère) is a painting by the French painter Jean-Antoine Watteau. It is also known as Voyage to Cythera and Pilgrimage to the Isle of Cythera.[1] Watteau submitted this work to the Royal Academy of Pain...

 

تعداد الولايات المتحدة 1920

تعداد الولايات المتحدة 1920 تعداد الولايات المتحدة 1920 المعلومات البلد الولايات المتحدة  الموقع الولايات المتحدة  التاريخ 5 يناير 1920  تعداد الولايات المتحدة 1910  تعداد الولايات المتحدة 1930  تعديل مصدري - تعديل   تعداد الولايات المتحدة 1920 كان التعداد الرابع عشر ل...

 

Istana Lunéville

Château de Lunéville (2011) Istana Lunéville atau Château de Lunéville adalah sebuah istana yang dimiliki oleh Adipati Lorraine semenjak abad ke-13. Istana ini dibangun kembali sebagai Versailles di Lorraine oleh Adipati Léopold dari tahun 1703 hingga 1723 berdasarkan rancangan Pierre Bourdict dan Nicolas Dorbay dan kemudian Germain Boffrand. Lunéville diklasifikasikan sebagai monumen bersejarah pada tahun 1901.[1] Kini apartemen bekas penguasanya dirawat oleh Kementerian Perta...

Sinan Erdem Dome

Sinan Erdem Spor Salonu Informasi stadionPemilikIstanbul Metropolitan Municipality - Spor A.Ş.LokasiLokasiBakırköy – Istanbul, TurkiKoordinat40°59′18.78″N 28°51′14.15″E / 40.9885500°N 28.8539306°E / 40.9885500; 28.8539306KonstruksiDibuka23 April 2010; 14 tahun lalu (2010-04-23)Biaya pembuatan€ 22 juta – biaya pembangunan awal (2003)$ 47 juta – biaya pembangunan penggantian model (2010)[1]($54 juta dalam dolar 2024 [2])Da...

 

مستكشفة المريخ المدارية

  ميّز عن مستكشف المريخ ومتجول استكشاف المريخ. مستكشفة المريخ المدارية   المشغل مختبر الدفع النفاث[1]  تاريخ الإطلاق 12 أغسطس 2005[2]  موقع الإطلاق مجمع إطلاق الفضاء 41 في محطة كيب كانافيرال للقوات الجوية[2]  الموقع الإلكتروني الموقع الرسمي  الميلان ...