Advanced Antenna Engineering

Class schedule

	Class schedule	HW assignments (Including preparation and review of the class.)	Amount of Time Required
1．	Outline of the course 1. Content 2. Objectives 3. Class schedule 4. Evaluation method and criteria	Textbooks and reference materials	190minutes
1．		One of the major objectives is antenna design. This process is highly appreciated, because it includes the topics for research on modern antenna technologies.
2．	Chapter 1. Antenna analysis 1.1 Overview 1.2 Antenna characteristics	Reference materials	190minutes
		Section 1.1 will be an overview, where the main points will be given in class. In Section 1.2 we will study antenna characteristics, which will be measured in Chapter 2.
		The antenna characteristics can be all evaluated on the basis of the current distribution. Consequently, the accuracy of the antenna characteristics depends on the determination of the correct current distribution. A method on obtaining the correct current distribution will be studied in Section 1.3.
3．	Chapter 1. Antenna analysis 1.3 Integral equation	Reference materials	190minutes
3．	Chapter 1. Antenna analysis 1.3 Integral equation	In Section 1.3, an overview will be given at the beginning so that you can grasp the idea of how an integral equation is obtained. Afterwards, some equations that are required for the derivation of the integral equation will be selected and will be proved in class. It is important to highlight that the integral equation is numerically solved to obtain the current distribution (see Section 1.4).
4．	Chapter 1. Antenna analysis 1.4 Numerical method (1) Functional equation (2) Expansion function (3) Linear operator	Reference materials	190minutes
4．		Functional equations such as integral equations and differential equations can be numerically solved. The basic idea is that the functional equation is reduced to a matrix form, which can be easily solved using a conventional technique. The general procedure will be shown with its examples.
5．	Chapter 1. Antenna analysis 1.4 Numerical method (4) Inner product (5) Convergence	Reference materials	190minutes
5．		A functional equation is eventually reduced to a matrix form, which consists of columns and rows. The columns are created when the unknown function is expanded using N expansion functions with N unknown coefficients. Note that we have the N unknown coefficients for only one equation. To determine the N unknown coefficients, the same number of equations (the rows in the matrix) is created when we take the inner product of the equation with N weighting functions.
6．	Chapter 2. Antenna measurement 2.1 Radiation pattern	Reference materials	190minutes
		The radiation pattern of a horn antenna will be measured in this class. The radiation pattern is defined as a plot of the radiation intensity versus position around the antenna at a fixed distance from the antenna. Measurements will be manually performed using a primitive system to enhance your studies.
		Measurement procedure is (1) to confirm how a transmitted signal is received in a measurement system, (2) measure the radiation pattern, and (3) draw the radiation patterns.
7．	Chapter 2. Antenna measurement 2.2 Polarization	Reference materials	190minutes
		We will measure the polarization of a loop antenna. The antennas are fed from different locations and some loops have perturbation elements for circular polarization. It is objective to know how the polarization of the loop antenna is determined by the feed location and with and without the perturbation element. The axial ratio is also measured as a function of frequency.
		Experiments will be made as follows. (1) Measure the polarization of five loop antennas. (2) Measure the frequency response of the axial ratio. (3) Discuss the results, answering quizzes.
8．	Chapter 2. Antenna measurement 2.3 Return loss	Reference materials	190minutes
		The return loss of a square patch antenna will be measured. The antennas have different side lengths L and feed locations F. Our aim is to find the appropriate values for L and F that will give the minimal return-loss at a test frequency.
		We will perform the following experiments. (1) Measure the side length L and feed location F of each antenna. (2) Measure the return loss of each antenna. (3) Find appropriate values of L and F that make the return loss minimal.
9．	Chapter 2. Antenna measurement 2.4 Antenna characteristics in anechoic chamber	Reference materials	190minutes
9．		Using the patch antenna measured in the previous experiment (see Section 2.3), we will measure its radiation characteristics, including the radiation pattern, polarization, and gain. Our objective here is to recognize how the gain depends on the return-loss characteristic. The experiment will be performed in an anechoic chamber for accurate measurements. Note that we will automatically measure the radiation characteristics using a modern system, rather than the primitive system used in the previous experiment (see Section 2.1).
10．	Chapter 3. Antenna design 3.1 Wide-band technique	Reference materials	190minutes
10．	Chapter 3. Antenna design 3.1 Wide-band technique	A novel antenna will be introduced as a radiation element. The element will be used in a reference antenna array afterwards. The reference antenna will then be modified for wide-band radiation. The frequency bandwidth should be wider than that of the reference antenna.
11．	Chapter 3. Antenna design 3.2 Multi-frequency technique	Reference materials	190minutes
11．	Chapter 3. Antenna design 3.2 Multi-frequency technique	We will introduce a single square antenna, whose corners are truncated for circular polarization. The square element will be used to construct a triple-square antenna with a single feed. The antenna should show three minima in the frequency response of the axial ratio.
12．	Chapter 3. Antenna design 3.3 High-efficiency technique	Reference materials	190minutes
12．	Chapter 3. Antenna design 3.3 High-efficiency technique	We will first analyze a novel loop antenna having parallel wires. The rotational sense of the circular polarization would depend on the feed location at the junction of the loop and parallel wires. Based of the radiation characteristics, we will design two types of loop antenna arrays whose radiation efficiencies would be higher than that of a conventional loop antenna array.
13．	Chapter 3. Antenna design 3.4 Low cross-polarization technique	Reference materials	190minutes
13．		A dual antenna having a symmetric configuration will be first presented. Next, an asymmetric dual antenna will be introduced for wide-band radiation. Finally, a planar array of the two asymmetric dual antennas will be designed to reduce cross-polarized radiation.
14．	Final assignment and its presentation	Textbooks and reference materials	190minutes
		You further have insight into one of the three topics (antenna analysis, measurement, and design) by yourself, and present your research (essay + presentation).
		You are required to hand in the above-mentioned essay as a final assignment and to make a final presentation on the essay.
Total.	-	-	2660minutes

	Final assignment	Final presentation	Total.
1.	20%	20%	40%
2.	10%	10%	20%
3.	20%	20%	40%
Total.	50%	50%	-