Name: impedance matching with mesh currents
Uploaded: 2024-04-11T12:48:49.000Z
Duration: 1 min 12 s
Channel: JoVE

無線通信では、インピーダンスマッチング回路によって無線送信機と受信機のインピーダンスが整列します。
抵抗と、並列に配置されたコンデンサとインダクタで構成される基本的なインピーダンス整合回路を考えてみましょう。
入力信号と出力信号がわかっている場合は、コンデンサを流れる電流を計算できます。
入力電圧の時間領域式から抽出された角周波数は、インダクタとコンデンサのインピーダンスを決定するために使用されます。
変換された周波数領域回路は、インピーダンスと入力信号と出力信号を極性形式で表します。
解析では、メッシュ電流が割り当てられ、キルヒホッフの電圧則が各メッシュに適用され、一連の線形連立方程式が得られます。
これらの方程式は行列形式で表すことができ、その後、Cramerの法則を使用してメッシュ電流を解くことができます。
共有ブランチの電流は、メッシュ電流の差です。
計算されたメッシュ電流を代入することにより、コンデンサの両端の電流は極性形式で取得され、その後時間領域に変換されます。

ac 回路のメッシュ解析

無線通信の領域では、インピーダンス整合の重要性を考慮する必要があります。 無線送信機と受信機の間で信号を効率的に伝送することが重要です。 このバランスを達成するには、抵抗、コンデンサ、およびインダクタからなる 1 つの基本構成を備えたインピーダンス整合回路を使用する必要があります。

これらのインピーダンスを調和させるプロセスは、入力信号と出力信号を明確に理解することから始まります。 これらの信号がわかったら、次のステップは、この回路のコンデンサを流れる電流を計算することです。

入力電圧の時間領域表現から抽出される角周波数は、重要な役割を果たします。 これは、インダクタとコンデンサのインピーダンス値を決定する際の指針となります。

<img alt="Equation1" src="/files/ftp_upload/15111/15111_PT_Equation_1.svg" style="text-align: center; height: 16px;">
<img alt="Equation2" src="/files/ftp_upload/15111/15111_PT_Equation_2.svg" style="text-align: center; height: 40px;">

次に、回路は周波数領域に変換されます。 この表現には、インピーダンス、入力信号と出力信号が含まれており、すべて極形式で表現されるため、解析が簡素化されます。 回路の動作をさらに詳しく調べるために、メッシュ電流が割り当てられ、メッシュ解析の基本原理であるキルヒホッフの電圧則 (KVL) が適用されます。 重要なのは、メッシュ解析は特に平面回路に適しているということです。

この綿密な分析の結果、行列形式でエレガントに表現できる一連の線形連立Figureが得られます。 クレイマーの法則が作用してメッシュ電流が明らかになり、コンデンサ全体で共有される電流を求められるようになります。

計算されたメッシュ電流を代入すると、コンデンサを流れる電流が得られ、最初は極形式で表されます。 結果、このデータは時間領域に巧みに変換され、インピーダンス整合回路を理解して最適化されます。

AC 回路のメッシュ解析

無線通信では、インピーダンスマッチング回路によって無線送信機と受信機のインピーダンスが整列します。
基本的なインピーダンス整合回路を考えてみましょう...

Education

JoVE Core

Electrical Engineering

電気工学

Unit 1

ユニット1

AC Circuit Analysis

交流回路解析

KEY TERMS AND CONCEPTS

主要用語と概念

Mesh Analysis for AC Circuits

impedance matching with mesh currents

Impedance matching in radio communication uses resistor, capacitor, and inductor circuits to help signals move efficiently between a transmitter and a receiver. The circuit must balance the input and output signals before the current in the capacitor can be found. This makes the problem a good example of AC circuit analysis for high school students.

The first step is to identify the input voltage and the output signal. The angular frequency is then taken from the time-domain form of the input voltage. That frequency is used to find the impedance of the inductor and the capacitor, since both depend on frequency in AC circuits.

Next, the circuit is moved into the frequency domain. In this form, the signals and impedances are written in polar form, which makes the math easier to handle. Mesh currents are then assigned to the planar circuit, and Kirchhoff's voltage law, or KVL, is applied around each loop.

The result is a set of linear equations. These equations can be written in matrix form. Cramer's rule is then used to solve for the mesh currents and find the current shared by the capacitor. After substituting the mesh currents, the capacitor current is converted from polar form back into the time domain to complete the impedance-matching analysis.

Impedance Matching with Mesh Currents

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AC Waveform Basics and Phase

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phasors

Phasors for AC Circuit Analysis

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AC Circuit Phasors: Resistor, Inductor, Capacitor

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Series and Parallel Impedance Rules

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mesh analysis for ac circuits

Impedance matching in radio communication uses resistor, capacitor, and inductor circuits to help signals move efficiently between a transmitter and a receiver. The circuit must balance the input and output signals before the current in the capacitor can be found. This makes the problem a good example of AC circuit analysis for high school students. The first step is to identify the input voltage and the output signal. The angular frequency is then taken from the time-domain form of the input...

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AC Source Conversion in Circuit Analysis

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Norton Current in AC Circuit Analysis

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key terms and concepts

Learn how mesh currents, KVL, and Cramer's rule are used to analyze an AC impedance-matching circuit and find capacitor current in radio communication.

Impedance Matching with Mesh Currents | JoVE K12

JoVE Core 電気工学 は、電気回路の基本概念と回路解析テクニックを網羅したアニメーションビデオシリーズです。オペアンプと回路変換および 1 次・ 2 次回路の概念を網羅しています。実験を撮影した実写動画では、設計例や現代社会での応用が含まれており、複雑な概念も分かりやすく学習いただけます。

electrical engineering

Impedance Matching with Mesh Currents

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