外輻射源雷達是一種采用第三方輻射源,在接收端同時接收直達波信號與目標回波信號,進而構建目標檢測的新體制雷達系統(tǒng)。本書系統(tǒng)地介紹了外輻射源雷達工程的相關處理方法及應用實例。全書共10 章,結(jié)合作者多年從事外輻射源雷達研究的理論成果和實際工程經(jīng)驗,對外輻射源雷達技術進行了全面系統(tǒng)的闡述。從外輻射雷達的基礎理論和方法出發(fā),介紹了外輻射雷達的發(fā)展歷史和現(xiàn)狀,系統(tǒng)總結(jié)了外輻射源雷達的組成部分,深入研究了外輻射雷達目標探測、相干積累、檢測算法、目標定位跟蹤等信號處理技術,同時也梳理了外輻射源目標散射機理和電磁傳播環(huán)境建模等重要研究。
雷達是一種用于測量目標距離、速度和方向的電子設備,在現(xiàn)代戰(zhàn)爭、天氣預報、
民用航空等領域已經(jīng)得到廣泛應用。尤其是在現(xiàn)代戰(zhàn)場中,雷達裝備往往決定了作戰(zhàn)方
對整個戰(zhàn)場信息的掌控能力,是決定能否取勝的核心因素之一。然而,隨著現(xiàn)代軍事科
技的不斷進步,電磁環(huán)境日益復雜,各類新型電子對抗技術,特別是反輻射武器的出現(xiàn),
給傳統(tǒng)雷達帶來了巨大的挑戰(zhàn)。
外輻射源雷達是一種采用第三方輻射源,在接收端同時接收直達波信號與目標回波
信號,進而實現(xiàn)目標檢測的新體制雷達系統(tǒng)。其具有收發(fā)端分置、接收端無源工作的特
點,因此具有較好的抗干擾、抗反輻射武器、抗隱身目標和抗低空突防等優(yōu)勢,是應對
靜默電子戰(zhàn)、低零功率作戰(zhàn)等新作戰(zhàn)環(huán)境的重要手段之一。但是,外輻射源雷達相關技
術存在以下難題。
首先,目標結(jié)構復雜,邊界條件多樣,與空間環(huán)境電磁耦合嚴重,導致目標電磁散
射機理復雜,難以高效、精確地求解多尺度電大尺寸目標的電磁散射特性。在當前作戰(zhàn)
環(huán)境中,可用的外輻射源頻段跨度極大,從較低頻段的FM 廣播信號到Ku/Ka 頻段的衛(wèi)
星信號,多尺度目標的電磁散射特性隨頻率的電磁改變而產(chǎn)生極大的差異,再加上收發(fā)
分離的幾何結(jié)構特點,使目標散射特性分析維度極大地增加,難以建立統(tǒng)一適用的目標
電磁散射特性表征分析理論。
其次,目標散射信號受雜波影響大,目標信號與雜波能量差異較大,雜波難以抑制。
為了保證目標的全天時、全天候應用,外輻射源雷達通常采用民用通信信號。這些信號
較寬的發(fā)射波束使不同地形地貌的雷達雜波更加復雜,極易掩蓋目標。同時,這些雜波
也會影響直達波信號的接收,降低相參積累增益。通信系統(tǒng)獨特的用頻規(guī)劃和信號幀結(jié)
構等設置,也加大了目標檢測的難度。例如,我國地面數(shù)字電視輻射源通常在不同站點
同時發(fā)射完全相同的信號。這樣的模式設置不僅會進一步提高雜波的復雜度,而且會產(chǎn)
生大量虛假目標,影響目標檢測結(jié)果。
再次,電磁散射信號極其微弱,難增強合成,難積累。外輻射源本身通常不是為目
標檢測而設置的,較大的覆蓋范圍與較低的發(fā)射能量使目標回波信噪比極低。雖然電磁
空間存在大量輻射源,但是這些輻射源信號特性各異,難以有效地增強合成,提高增益。
同時,由于目標回波信噪比極低,外輻射源雷達往往需要更長的積累時間,高速運動目
標會使長積累時間的回波產(chǎn)生極大的差異,從而導致目標能量分散,目標檢測難度提高。
最后,目標信號傳播環(huán)境復雜,難以精確地建模。由于電離層的非線性和時空變化
性質(zhì),目標電離層的分析需要充分考慮不同時段和不同位置的電離層參數(shù)的變化,同時
需要對大氣層中的干擾因素進行充分的分析和消除,以獲得準確的電離層數(shù)據(jù);夭ㄐ
號非常微弱,因此需要對電離層中的噪聲進行充分的分析和消除,以保證目標信號的準
確性和可靠性。
本書主要針對以上難點和挑戰(zhàn),全面介紹和深入研究相關的技術細節(jié)。首先介紹了
外輻射源雷達的發(fā)展歷史和現(xiàn)狀。然后介紹了外輻射源雷達的基本理論與方法。接著詳
細介紹了外輻射源雷達典型目標的電磁散射模型。之后詳細地介紹了參考信號提純、雜
波抑制、相參積累、信號合成與增強等數(shù)字信號處理理論及方法。最后介紹了外輻射源
雷達電波傳播對外輻射源雷達探測性能的影響,并詳細介紹了基于衛(wèi)星外輻射源的目標
探測定位技術。作者希望本書對外輻射源雷達相關技術的研究,能提高我國在新作戰(zhàn)環(huán)
境下的電子作戰(zhàn)能力和作戰(zhàn)效能,為相關設備的研制提供理論和技術基礎。
由于個人能力有限,書中難免有疏漏之處,懇請各位讀者批評指正。
劉春恒
2024 年3 月
第1 章 緒論····························································································.1
1.1 外輻射源雷達概述··········································································.1
1.1.1 外輻射源雷達與外輻射源雙站雷達·············································.1
1.1.2 外輻射源雙站雷達的特性·························································.2
1.1.3 外輻射源雙站雷達面臨的挑戰(zhàn)···················································.7
1.2 外輻射源雙站雷達的發(fā)展歷史···························································.9
1.3 本書內(nèi)容安排··············································································.16
第2 章 外輻射源雷達技術········································································.17
2.1 外輻射源雷達方程········································································.17
2.1.1 噪聲條件下的外輻射源雷達方程··············································.17
2.1.2 雜波條件下的外輻射源雷達方程··············································.23
2.2 互模糊函數(shù)相參積累·····································································.29
2.2.1 互模糊函數(shù)的特性································································.29
2.2.2 互模糊函數(shù)的經(jīng)典計算方法····················································.31
2.2.3 時域補償批處理法································································.36
2.3 主要外輻射源信號與模糊函數(shù)特征···················································.48
2.3.1 DVB-S 信號········································································.48
2.3.2 GPS 信號············································································.51
2.3.3 FM 信號·············································································.53
2.3.4 DVB-T 信號········································································.54
2.3.5 DTMB 信號·········································································.56
2.3.6 5G 信號·············································································.59
2.3.7 不同外輻射源雷達信號探測的影響分析與性能比較······················.61
2.4 外輻射源雷達系統(tǒng)架構及信號處理流程·············································.64
2.4.1 外輻射源雷達系統(tǒng)架構··························································.64
2.4.2 外輻射源雷達信號處理流程····················································.67
第3 章 外輻射源目標電磁散射機理與電磁散射特性·······································.70
3.1 概述··························································································.70
3.2 外輻射源典型目標的散射源及電磁散射機理·······································.71
3.2.1 鏡面反射············································································.71
3.2.2 二面角反射·········································································.72
3.2.3 腔體散射············································································.74
3.2.4 邊緣繞射············································································.75
3.2.5 尖端繞射············································································.77
3.2.6 爬行波繞射·········································································.78
3.2.7 表面不連續(xù)處的散射·····························································.80
3.3 目標電磁散射特性計算方法····························································.82
3.3.1 高頻近似方法······································································.82
3.3.2 全波計算方法······································································.87
3.4 多尺度電大尺寸目標電磁散射特性計算方法·······································.92
3.4.1 基于區(qū)域分解的矩量法(SMoM) ···········································.93
3.4.2 基于區(qū)域分解的自適應積分方法(SAIM) ································.96
3.4.3 基于并行計算的區(qū)域分解MLFMA ···········································.99
3.4.4 高低頻混合算法··································································.103
3.5 典型目標BCS 特征分析································································.109
3.5.1 隱身飛機BCS 和RCS 對比····················································.109
3.5.2 波音737-400 民航客機BCS 特征分析······································.110
第4 章 目標散射中心提取與目標電磁散射特征反演·······································113
4.1 概述·························································································.113
4.2 散射中心模型·············································································.114
4.2.1 散射中心模型概述·······························································.114
4.2.2 點散射中心模型··········