發(fā)布時(shí)間：2018-10-14 12:21

【摘要】：隨著地理位置服務(wù)的發(fā)展,室內(nèi)定位技術(shù)有著廣闊的應(yīng)用前景,如室內(nèi)監(jiān)控、商場(chǎng)導(dǎo)航等。超寬帶技術(shù)由于系統(tǒng)結(jié)構(gòu)簡(jiǎn)單、抗多徑、穿透性強(qiáng)、測(cè)距精度高、共存性好,在復(fù)雜多徑環(huán)境下的室內(nèi)定位中占有優(yōu)勢(shì),因而成為近十年來(lái)的研究熱點(diǎn)。但是,該技術(shù)在復(fù)雜環(huán)境下超寬帶信號(hào)傳播特性分析、實(shí)用高精度測(cè)距算法設(shè)計(jì)等方面仍面臨諸多難題。超寬帶定位技術(shù)還可應(yīng)用于戰(zhàn)場(chǎng)偵察與監(jiān)視。相對(duì)于單基地高頻地面?zhèn)刹炖走_(dá),多基地超寬帶地基偵察雷達(dá)具有很多優(yōu)勢(shì),如抗摧毀、抗干擾、可探測(cè)隱蔽目標(biāo)等,是戰(zhàn)場(chǎng)偵察雷達(dá)的重要發(fā)展方向。在近程多基地超寬帶雷達(dá)中,如何在復(fù)雜未知環(huán)境下實(shí)現(xiàn)對(duì)運(yùn)動(dòng)人員的可靠定位與持續(xù)穩(wěn)健跟蹤是其關(guān)鍵技術(shù)問(wèn)題和重要研究?jī)?nèi)容。本文針對(duì)室內(nèi)和樹(shù)林等多徑環(huán)境,結(jié)合多項(xiàng)科研項(xiàng)目,對(duì)超寬帶技術(shù)在目標(biāo)定位與跟蹤中的應(yīng)用問(wèn)題展開(kāi)研究。研究?jī)?nèi)容包括復(fù)雜環(huán)境下超寬帶信號(hào)傳播特性、實(shí)用的超寬帶測(cè)距算法、多基地系統(tǒng)理論上的定位及跟蹤性能、多基地定位中虛假定位點(diǎn)剔除和多目標(biāo)定位、多徑環(huán)境下多基地穩(wěn)健跟蹤等。經(jīng)仿真和實(shí)測(cè)數(shù)據(jù)驗(yàn)證的研究成果可以應(yīng)用到超寬帶定位、多基地戰(zhàn)場(chǎng)偵察雷達(dá)設(shè)計(jì)、多基地定位和跟蹤等方面。1、針對(duì)測(cè)距和定位應(yīng)用,分析了IEEE 802.15.4a信道模型在不同環(huán)境下的部分統(tǒng)計(jì)特性,如首徑后第1條多徑的位置及幅度分布、首徑后2ns內(nèi)多徑的條數(shù)及幅度的分布等,所得結(jié)論為測(cè)距算法設(shè)計(jì)奠定了基礎(chǔ)。提出了兩段多徑模型以描述脈沖超寬帶信號(hào)在發(fā)射站—非合作目標(biāo)—接收站間傳播時(shí)的信道特性�；趯�(shí)測(cè)數(shù)據(jù)分析了超寬帶信號(hào)的穿墻傳播特性,結(jié)果表明多徑在超寬帶信號(hào)穿墻傳播中存在。對(duì)背景相消后的剩余回波分析證明了復(fù)雜環(huán)境下被監(jiān)視目標(biāo)運(yùn)動(dòng)時(shí),存在與目標(biāo)相關(guān)的多徑現(xiàn)象。同時(shí),由于環(huán)境的改變,特別是相對(duì)位置關(guān)系的變化,會(huì)導(dǎo)致跟隨目標(biāo)的多徑發(fā)生變化。2、為降低TOA估計(jì)性能對(duì)門(mén)限的嚴(yán)格要求,提出了能量檢測(cè)接收機(jī)下簡(jiǎn)單實(shí)用的脈沖超寬帶TOA估計(jì)新方法。該方法利用了接收信號(hào)統(tǒng)計(jì)特性,即不同幀噪聲樣本超過(guò)門(mén)限的隨機(jī)性和首徑樣本的確定性。在密集多徑環(huán)境下,提出了一種基于熵的無(wú)需門(mén)限的首徑檢測(cè)新方法。該方法從另一個(gè)角度考慮首徑樣本檢測(cè)問(wèn)題。通過(guò)對(duì)信道的分析,可知密集多徑環(huán)境下多徑區(qū)域具有穩(wěn)定性,特別是首徑附近,新方法通過(guò)檢測(cè)熵序列的突變檢測(cè)多徑區(qū)域,進(jìn)而確定首徑樣本。為避免使用復(fù)雜的chi平方分布,本文提出對(duì)ED接收機(jī)輸出樣本序列進(jìn)行冪變換,然后擬合變換數(shù)據(jù)序列的分布,在最佳近似分布基礎(chǔ)上估計(jì)TOA,獲得了與基于較復(fù)雜的理論上的chi平方分布的TOA估計(jì)方法類(lèi)似的性能。分析了ED接收機(jī)部分參數(shù),并提出了基于延時(shí)器的具有更高精度的TOA估計(jì)方法。3、從理論上系統(tǒng)地分析了多基地雷達(dá)系統(tǒng)兩個(gè)方面的性能:不同狀態(tài)的可觀(guān)測(cè)性和不同狀態(tài)估計(jì)的CRLB。分別分析了兩種情形下的可觀(guān)測(cè)性,多站瞬間位置和速度的可觀(guān)測(cè)性以及不同航跡的跟蹤可觀(guān)測(cè)性。分別分析推導(dǎo)了多基地下瞬間目標(biāo)狀態(tài)估計(jì)的CRLB和跟蹤的CRLB。理論分析和仿真結(jié)果可以為系統(tǒng)設(shè)計(jì)提供指導(dǎo)。4、在分析多基地下單接收站距離或多普勒觀(guān)測(cè)誤差變化對(duì)定位和測(cè)速的影響基礎(chǔ)上,首先提出并推導(dǎo)了速度一致性準(zhǔn)則,即在同一個(gè)時(shí)間,目標(biāo)只可能處于一個(gè)位置,速度大小和方向應(yīng)唯一。不同觀(guān)測(cè)組合估計(jì)得到的目標(biāo)速度應(yīng)是一致的,而虛假觀(guān)測(cè)組合估計(jì)的數(shù)個(gè)速度不一致。據(jù)此可判別真假觀(guān)測(cè)組合,然后基于真假組合的判定和速度一致性完成不同站觀(guān)測(cè)的正確配對(duì)和多目標(biāo)定位。仿真結(jié)果表明該方法具有很高的虛假組合識(shí)別成功率。5、提出了多徑環(huán)境下的基于軌跡關(guān)聯(lián)性的真假目標(biāo)軌跡辨識(shí)算法,該算法把伴隨動(dòng)目標(biāo)的多徑回波信號(hào)看作來(lái)自一個(gè)虛假目標(biāo),根據(jù)雙站距離和和多普勒觀(guān)測(cè)得到目標(biāo)的當(dāng)前航跡,然后求出反射點(diǎn),根據(jù)路徑關(guān)系識(shí)別真實(shí)軌跡和虛假軌跡,當(dāng)目標(biāo)向基線(xiàn)靠近時(shí)識(shí)別率較高。在穩(wěn)健跟蹤方面,為應(yīng)對(duì)數(shù)據(jù)缺失和問(wèn)題觀(guān)測(cè),設(shè)計(jì)了不同觀(guān)測(cè)維度下的穩(wěn)健跟蹤流程,該流程通過(guò)自適應(yīng)改變?yōu)V波器結(jié)構(gòu)實(shí)現(xiàn)對(duì)目標(biāo)的持續(xù)跟蹤;為應(yīng)對(duì)干擾等帶來(lái)的錯(cuò)誤觀(guān)測(cè),提出了基于錯(cuò)誤觀(guān)測(cè)組合辨識(shí)的復(fù)雜環(huán)境下穩(wěn)健跟蹤方法,其使用預(yù)測(cè)與觀(guān)測(cè)最鄰近、速度和位置一致性準(zhǔn)則來(lái)辨識(shí)錯(cuò)誤組合。針對(duì)實(shí)際戰(zhàn)場(chǎng)上常見(jiàn)的之字形戰(zhàn)術(shù)機(jī)動(dòng)人員機(jī)動(dòng)跟蹤問(wèn)題,提出了基于分段CV模型的IMM算法。新方法建立了機(jī)動(dòng)人員的運(yùn)動(dòng)模型,可更加準(zhǔn)確的描述目標(biāo)真實(shí)的運(yùn)動(dòng)狀態(tài)。所提方法中的模型集可以及時(shí)適應(yīng)目標(biāo)運(yùn)動(dòng)方向的變化,在突變發(fā)生時(shí)可對(duì)跟蹤模型集的速度方向不斷調(diào)整直至達(dá)到穩(wěn)態(tài),使?fàn)顟B(tài)分量估計(jì)更接近目標(biāo)真實(shí)的速度方向。仿真表明所提算法可以獲得比傳統(tǒng)機(jī)動(dòng)算法更好的跟蹤性能。
[Abstract]:With the development of geographical location service, indoor positioning technology has wide application prospect, such as indoor monitoring, market navigation and so on. Ultra-wideband technology has the advantages of simple system structure, multi-diameter, strong penetrability, high ranging precision and good coexistence, and has an advantage in indoor positioning under complex multi-path environment, thus becoming a hot spot in the last decade. However, this technology still faces many difficulties in the analysis of ultra-wide band signal propagation characteristics, practical high precision distance measurement algorithm design and so on in complex environment. Ultra-wideband positioning technology can also be applied to battlefield reconnaissance and surveillance. Compared with single-base high-frequency ground reconnaissance radar, multi-base ultra-wideband ground reconnaissance radar has many advantages, such as anti-destruction, anti-jamming, detection of hidden targets and so on, and is an important development direction of battlefield reconnaissance radar. In short-range multi-base ultra-wideband radar, how to realize reliable positioning and continuous robust tracking of moving personnel in complex unknown environment is its key technology problem and important research content. In view of the multi-path environment such as indoor and wood, combining several scientific research projects, this paper studies the application of ultra-wideband technology in target positioning and tracking. The research content includes the characteristics of ultra-wide band signal propagation in complex environment, practical ultra-wideband distance measuring algorithm, positioning and tracking performance in multi-base system theory, false localization point elimination in multi-base location and multi-target positioning, multi-base robust tracking in multi-path environment, etc. The results of simulation and data verification can be applied to the aspects of ultra-wide band positioning, multi-base battlefield reconnaissance radar design, multi-base location and tracking, etc. 1. For ranging and location applications, some statistical properties of IEEE 802.15. 4a channel model in different environments are analyzed. The results are as follows: the location and amplitude distribution of the first multi-path, the number of multi-paths and the distribution of the amplitude within 2ns after the first diameter, and the conclusion is the foundation for the design of the distance-measuring algorithm. A two-stage multi-path model is proposed to describe the channel characteristics of a pulsed ultra-wideband signal propagating between a transmitting station and a non-cooperative target transceiver station. Based on the measured data, the wall propagation characteristics of ultra-wideband signals are analyzed, and the results show that the multi-path exists in the through-wall propagation of ultra-wideband signals. The residual echo analysis after the background cancellation proves that there is a multi-path phenomenon related to the target when the target motion is monitored in a complex environment. At the same time, due to the change of the environment, especially the relative positional relation, the multi-path change of the following target can be caused, and the new method of the simple and practical pulse ultra-wideband TOA estimation under the energy detection receiver is proposed in order to reduce the requirement of TOA estimation performance to the threshold. The method utilizes the statistical characteristic of the received signal, that is, the randomness of the different frame noise samples exceeds the threshold and the certainty of the first path sample. In the dense multi-path environment, a new method for detecting head diameter without threshold based on entropy is proposed. The method considers the first-diameter sample detection problem from another point of view. Through the analysis of the channel, it can be seen that the multi-path region has stability, especially near the first diameter, in the dense multi-path environment, and the new method detects the multi-path region by detecting the mutation of the entropy sequence, and then determines the first diameter sample. In order to avoid the use of complex chi-square distribution, this paper proposes a power transformation to the output sample sequence of ED receiver, then fits the distribution of transform data sequence, and estimates TOA on the basis of the optimal approximate distribution. A similar performance to TOA estimation methods based on a more complex theoretical chi-square distribution is obtained. In this paper, some parameters of ED receiver are analyzed, and a TOA estimation method based on delayer is proposed. The performance of two aspects of multi-base radar system is systematically analyzed theoretically: the observability of different states and the CRLB of different state estimation. The observability of two cases, the observability of multi-station instantaneous position and velocity, and the tractability of different flight paths are analyzed respectively. CRLB and CRLB for tracking target state estimation under multi-base are analyzed respectively. Theoretical analysis and simulation result can provide guidance for system design. 4. On the basis of analyzing the influence of distance or Doppler observation error of single receiving station on positioning and velocity measurement, this paper first puts forward and deduces the speed consistency criterion, that is, at the same time, The target may only be in one position, and the speed and direction should be unique. The target velocities obtained by different observation combinations are consistent, and several velocities of false observation combinations are inconsistent. and then the correct pairing and multi-target positioning of different station observations are completed based on the judgment and the speed consistency of the true and false combination. The simulation results show that the method has a high success rate of false combination recognition. 5. An algorithm based on track correlation based on track correlation in multi-path environment is proposed, which treats the multi-path echo signal with moving target as a false target. According to the two-station distance and the Doppler observation, the current track of the target is obtained, then the reflection point is obtained, the real track and the false track are identified according to the path relation, and the recognition rate is higher when the target is close to the baseline. In the aspect of robust tracking, in order to cope with the data loss and problem observation, a robust tracking process in different observation dimensions is designed, which realizes the continuous tracking of the target through the adaptive changing filter structure, and the error observation caused by the interference and the like is achieved, A robust tracking method based on error observation combined identification is presented, which uses prediction and observation nearest neighbor, velocity and position consistency criterion to identify the error combination. In this paper, a new IMM algorithm based on segmented CV model is proposed. The new method establishes the motion model of maneuver personnel, and can describe the target's real motion state more accurately. The model set in the proposed method can adapt to the change of the target motion direction in time, and the speed direction of the tracking model set can be continuously adjusted until the steady state is reached when the mutation occurs, so that the state component estimation is closer to the target real speed direction. Simulation results show that the proposed algorithm can achieve better tracking performance than traditional maneuvering algorithm.
【學(xué)位授予單位】：國(guó)防科學(xué)技術(shù)大學(xué)
【學(xué)位級(jí)別】：博士
【學(xué)位授予年份】：2014
【分類(lèi)號(hào)】：TN957.51
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本文編號(hào)：2270436