1、-The Technological Maturity of Chinese AESA Technology & Strategic Impacts中國有源相控陣技術開展狀況及其戰略影響Image 1: APG-63(V)2 radar installed on an F-15C. The APG-63(V)2 was the first fighter mounted AESA radar to enter service worldwide. The first American F-15C unit to receive the new radars were stationed

2、 at Elmendorf in 2000. In parison, the first European AESA entered operational service in 2021 and the first Russian AESA equipped fighters (Mig-35) will not enter service until 2021. The initial US technological lead in AESA technology is attributable to substantial investments made in the late sta

3、ges of the Cold War. 圖1：裝備F-15C的APG-63(V)2型雷達。APG-63(V)2是世界圍最先裝備戰斗機并投入使用的雷達。位于埃爾門多的美國F-15C單位夫于2000年最先接收該新型雷達。相比較而言，歐洲最早列裝使用AESA雷達的時間是2021年，而俄羅斯的Mig-35戰斗機于2021年前不會裝備AESA雷達。美國在AESA技術上的領導地位，完全得益于冷戰后期的巨額投資。Author's Note: During the research process on the J-31s avionics (for the uping Threat An

4、alysis of Foreign Stealth Fighters:J-31 Part II), it became apparent that very few credible, verifiable, and non-speculative English based source materials e*isted on the subject of PLA fighter radars. Basic information, such the proper name or designation of a radar system is utilized by a particul

5、ar fighter often varies between sources; performance figures associated with domestically produced radars is even harder to verify. This article's intent was to pile a wide variety of information on e*pected future developments in Chinese actively scanned electronic array (AESA) radars. Furtherm

6、ore, the current “Threat Analysis of Foreign Stealth Fighters: Part I Chengdu J-20 is largely dated with respect to developments with the J-20s avionics suite and this article subsequently provides more up-to-date information on the J-20s AESA. 作者注：在J-31航空電子設備研制過程中在?國外隱身戰機威脅分析第二局部：飛J-31?中將進展說明，

7、目前尚沒有多少足夠可信，或經證實，以及非投機性的解放軍戰斗機雷達資料。一些根底信息，例如裝備特定戰斗機的雷達系統的名稱或型號與其生產廠商有關；中國國產雷達的性能參數很難被證實。本文的主要目的在于收集匯總有關中國有源相控陣雷達未來開展方向的廣泛大量信息。此外，當前?國外隱身戰機威脅分析第一局部：成飛J-20?中已經對J-20的航電系統的開展狀態進展了大量描述，本文隨后將提供有關J-20有源相控陣雷達開展的最新信息。AESA radars represent a significant increase in detection power, reliability, and electronic

8、 warfare capabilities when pared to older electronically scanned arrays (ESA) and mechanically scanned arrays (MSA). This article largely focus on more technical aspects of AESAs but the basics of AESAs are cogently detailed by Karlo Kopp in "Active Electronically Steered Arrays A Maturing Tech

9、nology".比照擬早的電子掃描陣列無源相控陣雷達和機械掃描雷達，有源相控陣雷達具有在探測性能、可靠性和電子戰方面均有大幅提升。本文主要關注AESA技術，但該技術的更詳細描述可參考Karlo Kopp的?有源相控陣列一個成熟的技術?一文。Three main determinants dictate the ma*imum number of transmit receiver modules a fighter radar can acmodate: the volume of the aircrafts nose, the technological maturity of t

10、he firm/countrys T/R module packaging technology, and the effectiveness of the radar's thermal management system(s). The volume of the nose is a fairly intuitive constraint, the larger an aircrafts nose is, the larger the radar can be. For e*ample, the F-15Cs nose cone is able to acmodate the mu

11、ch larger 1,500 T/R element APG-63V(3) radar vs. the F-16C Block 60 with its paratively smaller nose cone and its 1,000 T/R element APG-80 AESA. Packaging technology refers to how many individual T/R modules can be installed within the finite space usually acplished by reductions in size of the indi

12、vidual T/R modules. The more technologically advanced a firms T/R packaging technology is, the smaller the individual T/R modules will be resulting in an increase density of the layout of T/R modules within the array. Thus, advancements in packaging technology enable engineers to acmodate more T/R m

13、odules within the fi*ed volume of the aircraft's nose.三個主要因素決定了戰斗機雷達可容納的T/R組件數量：飛機機頭的容積容量、T/R組件封裝技術的成熟度，以及雷達的熱管理系統的工作效率。機頭部位的容積是一個相當直觀的約束條件，飛機鼻錐部位容積越大，雷達天線陣面越大。例如：F-15C的機頭鼻錐可容納具有1500個T/R組件的APG-63V(3)雷達，而F-16C Block 60只能容納具有1000個T/R組件的APG-80雷達。通過減小單個T/R組件的體積，封裝技術決定了再固定的空間可容納的最大T/R組件數量。更加先進的封裝技術可制

14、造體積更小的T/R組件，從而提高了陣面上的T/R組件布局密度。因此，在封裝技術上的進步，將允許工程師們在固定的飛機鼻錐空間里布置更多的T/R組件。Image 2: US early production quad packed transmit receiver modules. The United States no longer produces quad channel T/R modules and has since produced single T/R module designs. Less advanced AESAs such as the Zhuk-AE utilize

15、 multi-T/R channel designs, it is possible China's first generation of AESAs also utilize a multi-T/R channel design.圖2：早期美國制造的4聯裝T/R組件。美國不再制造4聯裝T/R組件，轉而制造獨立封裝的T/R組件。少數先進AESA系統，例如：Zhuk-AE雷達，使用多聯裝T/R組件封裝技術，中國第一代AESA系統可能也使用了多聯裝T/R組件設計。Lastly, thermal management systems are instrumental for the ope

16、ration of high power AESA radars. Unlike MSA systems, air cooling systems are insufficient to prevent heat related system failures and frequent maintenance issues:最后，熱管理系統在高功耗AESA雷達中起到關鍵作用。與機械掃描MSA系統不同，風冷散熱系統缺乏以防止散熱相關的系統故障以及由其引起的頻繁維修費用：“Due to the behavior of microwave transistor amplifiers, the pow

17、er efficiency of a TR module transmitter is typically less than 45%. As a result, an AESA will dissipate a lot of heat which must be e*tracted to prevent the transmitter chips being molten pools of Gallium Arsenide - reliability of GaAs MMIC chips improves the cooler they are run. Traditional air co

18、oling used in most established avionic hardware is ill suited to the high packaging density of an AESA, as a result of which modern AESAs are liquid cooled.US designs employ a polyalphaolefin (PAO) coolant similar to a synthetic hydraulic fluid. A typical liquid cooling system will use pumps to driv

19、e the coolant through channels in the antenna, and then route it to a heat e*changer. That might be an air cooled core (radiator style) or an immersed heat e*changer in a fuel tank - with a second liquid cooling loop to dump heat from the fuel tank. In parison with a conventional air cooled fighter

20、radar, the AESA will be more reliable but will require more electrical power and more cooling, and typically can produce much higher transmit power if needed for greater target detection range performance (increasing transmitted power has the drawback of increasing the footprint over which a hostile

21、 ESM or RWR can detect the radar Kopp, 2021“由于微波發射放大器的特性，T/R組件中發射局部的用電效率典型值小于45%。因此，AESA系統工作期間所產生的大量熱量需要耗散，以防止發射局部芯片變為砷化鎵“熔爐高可靠性的砷化鎵微波單片集成電路需配備更佳的散熱器。在眾多已裝備的航電機載設備中所使用的傳統風冷技術，并不適用于高密度封裝的AESA系統，因此，現代AESA系統采用液冷技術。美國設計研發的聚-烯烴PAO冷卻液是一種合成液壓液。典型的液冷系統往往采用一個液壓泵驅動冷卻液在天線的散熱管道中流動，并最終通過冷卻液將熱量傳遞給熱交換機。這種熱交換機可以是類似

22、汽車引擎散熱器的風冷器，也可以是安放在油箱中的浸入式熱交換器。相比較傳統風冷戰斗機雷達而言，AESA系統將更加可靠，但同時需要更高的功耗和更苛刻的散熱需求，通過發射更高功率電磁波信號，就可以獲得更遠的目標探測距離性能但更高的發射功率同樣意味著雷達系統可能更早被敵方ESM或RWR設備偵測而暴露。-Kopp，2021。Image 3:The image which allegedly describes the number of TR modules within the J-10B, J-16, and J-20 has been posted on numerous defense foru

23、ms since at least December of 2021.圖3：該圖展示了截止2021年12月前在眾多軍事防御論壇廣泛登載的J-10B、J-16和J-20上AESA系統的T/R組件數量。Chinese defense forums have posted copies of the image above which claim to cite the J-20s AESA T/R module count at 1,856, the J-16s at 1,760, and the J-10B at 1,200 T/R modules. It is likely the J-10B

24、 is the first Chinese fighter aircraft to feature an AESA; J-10B units achieved initial operational capability (IOC) in October of 2021. The volume of the J-10s nose cone is not substantially different from that of the F-16 or the Israeli Lavi from which the J-10 is partially based. Therefore, if on

25、e were to assume China had reached parity with the United States in packaging technology, the 1,200 T/R module figure would be plausible but slightly high. For parison, the APG-80 AESA for the F-16C/D Block 60 has 1,000 T/R modules (DSB, 2001). However, it is unlikely that China has been able to rea

26、ch parity with the United States in terms of packaging technology on their first generation AESA design. Neither Russia nor Israel was able to field 1,000 T/R element arrays within their first generation fighter mounted AESAs for similar nose volumes as the F-16 with the Mig-35 and Israeli F-16 resp

27、ectively.中國軍事防御論壇上登載了圖片的副本，圖片聲稱J-20的AESA系統T/R組件數量為1856個，J-16為1760個，J-10B為1200個。J-10B飛機可能是首款使用AESA系統的中國國產戰斗機；J-10B單位在2021年10月形成初步作戰能力IOC。J-10飛機的鼻錐部位空間與F-16類同，或被J-10局部借鑒設計的以色列“獅戰機。因此，如果有人假設中國已經在封裝技術方面已經或局部到達美國的水平，則1200個T/R組件的數字可信度值得商榷，或至少略微被夸大了。作為比較，配裝F-16C/D Block 60的APG-80 AESA雷達系統擁有1000個T/R組件美國國防科技

28、局，2001。然而，中國在第一代AESA系統設計時的封裝技術似乎不可能到達美國同期水平。無論是俄羅斯還是以色列，以與F-16機頭鼻錐容積相類似的Mig-35和以色列F-16，在其第一代AESA雷達系統中均未能放置1000個T/R組件。Russias first fighter mounted AESA radar, the Zhuk-AE, contained 652 T/R modules and was unveiled in 2007. The Israeli ELM-2052 AESA radar, which has been marketed for both the F-16 a

29、nd the FA-50 a joint Korean Aerospace Industry and Lockheed Martin F-16 derivative, has roughly 512 T/R modules (Trimble, 2021). The only firm outside of the United States that was able to produce a 1,000 T/R element within one generation was the French avionics firm Thales with its RB2E radar (Avio

30、nics Today, 2021). While the relative technological maturity of European, Israeli, and Russian AESAs is not directly indicative of the relative technological maturity of Chinas packaging technology, it is an indicator that the first generation AESA produced by China is likely not on par with the US

31、which is generally recognized as having the most technological mature T/R packaging technology (Kopp, 2021).俄羅斯首款裝備戰斗機的AESA雷達Zhuk-AE，包含652個T/R組件，并在2007年首次公開亮相。以色列的ELM-2052 AESA雷達，在F-16和FA-50戰斗機上都擁有一定市場后者是國聯合航空工業集團在洛克希德馬丁公司F-16上研發的一款戰機，據估計，該型雷達擁有約512個T/R組件Trimble公司，2021。除美國外鄉公司外，只有法國航空業Thales公司在第一代AE

32、SA雷達RB2E上使用超過1000個T/R組件Avionics Today雜志，2021。雖然歐洲、以色列和俄羅斯的AESA雷達系統所采用的封裝技術水平并不能直接說明中國的封裝技術水平，但他們可作為參考，并說明在第一代AESA雷達系統中，中國不可能擁有與美國一樣的技術水平，而美國被廣泛成認是掌握最先進專業T/R組件封裝技術的國家Kopp，2021。Image 4: T/R module count of US AESAs based upon the 2001 Defense Science Board report "Future DoD Airborne High-Frequen

33、cy Radar Needs/Resources"(link provided in Source 1 citation, refer to page 6). Image Credit: Air Power Australia, 2021.圖4：美國AESA系統T/R組件數量，數據來自美國國防科學委員會2001年報告?未來國防機載高頻雷達需求和資源?。The prospect of Chinas TR packaging technology being on par with US firms within a single generation of radars is even

34、 more dubious when one e*amines the preference for an incremental technological development within the Chinese aerospace industry. Several Chinese aviation authors have hypothesized that the J-10B serves as a “technological stepping stone with respect to the development of the more advanced J-20. Fo

35、r e*ample, Feng Cao argues the J-10B and the J-16 AESAs were likely used to test technology related to the J-20s AESA which would be a second generation Chinese design. By virtue of the larger nose volumes in the J-16 and J-20 airframes, it is highly probable the two aircraft will feature radars wit

36、h more T/R modules than the J-10Bs radar. 通過參考中國航空工業的漸增性開發模式不難推測，在單獨一代雷達中，中國的封裝技術水平很難趕超美國同行。許多中國航空作家都預測，與更加先進的J-20相比，J-10B只扮演了“技術墊腳石的角色。比方：朝峰音譯認為，J-10B和J-16的AESA系統為裝備J-20的AESA系統提供技術測試，而后者則是中國第二代有源相控雷達系統。憑借更寬闊的機頭鼻錐局部容量，J-16和J-20所裝備的AESA雷達可能擁有比J-10B更多數量的T/R組件。The J-16 utilizes the Su-27BS airframe whi

37、ch has room for a 0.9-1.1 meter aperture in the nose which is on par with the F-15 and F-22 in terms of volume (Kopp, 2021). The 1,500 element N036 Tikhomirov NIIP AESA has a similar aperture size to the electronically scanned array (ESA) Irbis-E radar featured in the Su-35 series of fighters which

38、shares the base Su-27 airframe. If the 1,760 T/R figure is correct it would indicate the Chinese aerospace industry has eclipsed Russian T/R module packaging technology as the N036 is arguably the most advanced Russian fighter mounted AESA. Similarly, the most advanced US fighter mounted AESAs such

39、as the APG-77(V)2 and APG-82(V)1 contain 1,500 T/R modules*. While the prospect of Chinese avionics firms reaching parity with US and Russian firms is more plausible within two generations of designs, the author is skeptical the 1,760 figure is correct given the unsubstantiated nature of the image a

40、nd the fairly substantial 260 T/R discrepancy between the J-16 radar figure pared to the most advanced US and Russian AESA designs. Therefore, the author speculates it would be more reasonable to assume a figure between 1,200 and 1,500 TR modules for the J-16 rather than the 1,760 figure.J-16采用了Su-2

41、7BS機身設計，在機頭鼻錐部擁有約0.9m至1.1m的孔徑，沉著量方面看，與F-15和F-22一樣Kopp，2021。提赫米洛夫儀器制造研究院制造的N036 AESA雷達系統擁有1500個T/R組件，與電子掃描陣列ESAIrbis-E雷達無源相控陣PESA孔徑尺寸相似，后者在與Su-27機身構造設計相仿的Su-35上使用。如果說裝備J-16的AESA雷達確實擁有1760個T/R組件，則這將說明中國航空工業在T/R組件封裝技術方面已經超越俄羅斯，因為N036雷達據信已是目前俄羅斯戰機裝備的最先進AESA雷達系統。相類似地，最先進的美式戰機所裝備的APG-77(V)2 和APG-82(V)1雷達同

42、樣擁有約1500個T/R組件。通過兩代AESA系統設計，中國航空工業技術水平趕超美國和俄羅斯同行的可能性值得疑心，因此，作者疑心1760個T/R組件的信息源于對未經證實圖片的武斷猜測，因而造成了J-16 AESA系統比美國和俄羅斯最先進AESA系統多260個T/R組件的說法。據此，作者推測，裝備J-16的AESA雷達系統大約擁有1200至1500個T/R組件，而不是網傳的1760個。Image 5: The si*th and most recent (as of January 2021 ) unveiled J-20 testing aircraft model "2021 &q

43、uot;.圖5：最新曝光2021 年1月的第六代J-20測試驗證機代號：2021 。The tentative designation for the J-20's AESA is the Type 1475. While the nose volume of the J-20 is certainly large, the jet overall is longer and heavier than the F-22, no credible figures for nose volume were available at the time of this publication.

44、 As with the J-16 T/R figure, the J-20 figure is substantially greater than that of the most advanced US and Russian designs. Even if the Nanjing Research Institute of Electronics Technology (NRIET) or the China Leihua Electronic Technology Research Institute (607 Institute) was able to develop suff

45、icient packaging technology that would enable 1,856 T/R modules within the J-20's nose, the density of the T/R modules would create significant cooling problems. For e*ample, Phazotron's single greatest difficulty in designing the Zuk-AE was the AESA's thermal management system (Kopp, 20

46、21). Without an effective cooling system, the Type 1475 would not be reliable at peak power output and would cause significant maintenance issues. Furthermore, with such a high number of T/R modules, the Type 1475 would be vulnerable to radar warning receiver (RWR) systems such as the ALR-94 without

47、 a very capable low probability intercept (LPI) mode.J-20 AESA系統方案設計為1475型。J-20的機頭鼻錐空間比F-22更大，該款噴氣式飛機機身更長，重量更大，目前，尚未見有關于機頭鼻錐部位具體容量參數的相關報道。鑒于J-16的T/R組件數量，J-20的T/R組件應該比當前最先進的美國和俄羅斯AESA雷達設計更多。即便電子技術研究所NRIET或中國雷華電子技術研究所607研究所擁有足夠先進的封裝技術將1856個T/R組件裝進J-20的鼻子，如此密度的T/R組件構造將造成嚴重的散熱問題。假設不能有效解決散熱問題，1475型雷達將不能提

48、供可靠的最大功率發射性能，并帶來重大的維護問題。此外，擁有如此大數量的T/R組件，使得1475型雷達很難使用低截獲模式，從而更容易被雷達告警接收機RWR系統偵獲，例如：ALR-94型RWR。Many discussions with respect to the "relative stealthiness" of fighter aircraft are limited to merely paring radar cross section estimates while entirely neglecting alternate means of detecting

49、aircraft such as RWRs or other emission locator systems. David A*e succinctly pares the process of how RWRs function to how a flash light carried by another person is easily visible in a dark room. AESAs emit a substantial amount of energy, especially designs with a greater number of T/R modules, wh

50、ich enables passive emission locator systems to detect an AESA. The addition of an LPI software for AESAs mitigates the risk of RWR detection.許多有關戰斗機“相對隱身性的討論，只限于比較雷達截面積評估，而完全無視了其他對空偵察手段，例如：雷達告警接收機RWR和其他輻射定位系統。David A*e將RWR的功能簡單類比為在黑暗房間中尋找一個隨身攜帶閃光燈的人。AESA系統輻射可觀的能量，特別是擁有更多數量T/R組件的AESA系統，更容易向被動輻射定位系統暴露自己的位置。在AESA系統中增加低截獲