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In this dissertation, an accurate characterization of a fabricated X-band transmit/receive (T/R) module is described with the process generating control data to correct amplitude and phase deviations in an active electronically scanned array (AESA) antenna unit. Also, Markov chains for active tracking which assigns additional track illuminations evenly between search illuminations for a radar system are presented. And some quantitative analyses on track formation range are discussed by using them.  
For the accurate characterization of T/R modules, the quantization error of a digitally controlled attenuator and phase shifter is considered using not theoretical values due to discrete sets of amplitude and phase states but measured values including implementation errors. By using the presented procedure for the characterization, each initial control bit of both the attenuator and the phase shifter is closest to the required value for each array element position. Also, each compensated control bit for the parasitic cross effect between amplitude and phase control is decided using the same procedure. Reduction of the peak sidelobe level of an array antenna is presented as an example to validate the proposed method.
For the quantitative analysis on track formation range, three Markov chains for active tracking with one, two, and three additional track beams are presented. Compared with track-while-search (TWS) tracking that uses scan-to-scan correlation at search illuminations for tracking a target, active tracking has shown the maximum improvement in track formation range of about 27.6%. It is also shown that the number and detection probability of additional track beams have a significant impact on the track formation range. For the consideration of radar resource management at the preliminary radar system design stage, the presented analysis method can be used easily without the need of Monte Carlo simulation.

CONTENTS

ABSTRACT	i
CONTENTS	iii
List of Figures	v
List of Table	viii
Chapter 1.	Introduction	1
Chapter 2.	Overview of an AESA Radar System	4
2.1 Introduction	4
2.2 Basic configuration of an AESA radar system	6
2.2.1 Comparison of MSA, PESA, and AESA radar systems	6
2.2.2 Key components in H/W aspect	9
2.2.3 Key components in S/W aspect	15
2.3 Key characteristics of an AESA radar system	19
2.3.1 Functional improvement	19
2.3.2 Performance improvement	21
2.4 Summary	23
Chapter 3.	Accurate Characterization of T/R Modules with Consideration of Amplitude / Phase Cross Effect	24
3.1 Introduction	24
3.2 Generation of control data in AESA antenna unit	26
3.3 Characterization of T/R modules	29
3.3.1 Method	30
3.3.2 Verification	34
3.4 Summary	39
Chapter 4.	Quantitative Analysis on Track Formation Range using Markov Chain	40
4.1 Introduction	40
4.2 Analysis on track formation range of TWS tracking	41
4.3 Analysis on track formation range of active tracking	48
4.4 Summary	61
Chapter 5.	Conclusions	62
References		64