This course covers three main topics of antennas in wireless communication systems. Those three are antenna analysis, its
measurement, and its design. We will also cover modern antenna technologies with the research papers.

The course is composed of three chapters:

Ch. 1. Antenna analysis

1.1 Overview, 1.2 Antenna characteristics, 1.3 Integral equation, 1.4 Numerical method

Ch. 2. Antenna measurement

2.1 Radiation pattern, 2.2 Polarization, 2.3 Return loss, 2.4 Antenna characteristics in anechoic chamber

Ch. 3. Antenna design

3.1 Wide-band technique, 3.2 Multi-frequency technique, 3.3 High-efficiency technique, 3.4 Low cross-polarization technique

The course is composed of three chapters:

Ch. 1. Antenna analysis

1.1 Overview, 1.2 Antenna characteristics, 1.3 Integral equation, 1.4 Numerical method

Ch. 2. Antenna measurement

2.1 Radiation pattern, 2.2 Polarization, 2.3 Return loss, 2.4 Antenna characteristics in anechoic chamber

Ch. 3. Antenna design

3.1 Wide-band technique, 3.2 Multi-frequency technique, 3.3 High-efficiency technique, 3.4 Low cross-polarization technique

We will first derive an integral equation that is needed for antenna analysis and will solve the equation using a numerical
technique. Next, we will study antenna characteristics and their measurements. At the end of the course, we will learn how
these are appreciated in research topics.

One of the major purposes of this class is antenna design. This process is highly appreciated, because it is crucial for research on modern antenna technologies. Bear in mind that you will choose one topic from the three (antenna analysis, measurement, and design). The chosen topic should be further studied on your own as a final assignment with its presentation. The presentations are made in the final class.

One of the major purposes of this class is antenna design. This process is highly appreciated, because it is crucial for research on modern antenna technologies. Bear in mind that you will choose one topic from the three (antenna analysis, measurement, and design). The chosen topic should be further studied on your own as a final assignment with its presentation. The presentations are made in the final class.

- At the end of the course, students will be able to

analyze antennas, - measure antenna characteristics, and
- design antennas.

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 |

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. |
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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 |

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 |

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 |

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 |

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 |

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 |

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 |

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 |

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% | - |

・Assessment method

Final assignment (50%) and its presentation (50%).

・Requirements to obtain the credit

(1) Hand in the final assignment in the final class.

(2) Make a final presentation on the assignment and successfully answer the questions after the presentation from the audience.

More than 60% from your final grade is needed to obtain the credit.

Final assignment (50%) and its presentation (50%).

・Requirements to obtain the credit

(1) Hand in the final assignment in the final class.

(2) Make a final presentation on the assignment and successfully answer the questions after the presentation from the audience.

More than 60% from your final grade is needed to obtain the credit.

International students in their bachelor's are not eligible to enroll in this subject.

Radio wave engineering

Radio wave engineering

- Course that cultivates a basic interpersonal skills

Work experience | Work experience and relevance to the course content if applicable |
---|---|

N/A | N/A |

Last modified : Sat Apr 16 04:03:44 JST 2022