What do the subscripts of S parameters represent?
The correct answer is A: The port or ports at which measurements are made. What do the subscripts of S parameters represent is the port or ports at which measurements are made. S parameter subscripts indicate which ports are involved. For amateur radio operators, this is important for RF measurements. Understanding this helps when using network analyzers.
Exam Tip
S parameter subscripts = port or ports at which measurements are made. Think 'S'ubscripts = 'S'ource and 'D'estination ports. S parameter subscripts indicate which ports are involved. Not time, not quality, not frequency order - just ports.
Memory Aid
"S parameter subscripts = port or ports at which measurements are made. Think 'S'ubscripts = 'P'orts. S parameter subscripts indicate which ports are involved. Important for RF measurements."
Real-World Application
S parameter subscripts: They represent the port or ports at which measurements are made. For example, S21 means signal from port 1 to port 2. The first number is the output port, the second is the input port. This is what subscripts represent - ports.
Key Concepts
Why Other Options Are Wrong
Option B: Incorrect. Relative time between measurements isn't what subscripts represent - subscripts indicate ports. Time isn't the meaning.
Option C: Incorrect. Relative quality of data isn't what subscripts represent - subscripts indicate ports. Quality isn't the meaning.
Option D: Incorrect. Frequency order of measurements isn't what subscripts represent - subscripts indicate ports. Frequency order isn't the meaning.
题目解析
The correct answer is A: The port or ports at which measurements are made. What do the subscripts of S parameters represent is the port or ports at which measurements are made. S parameter subscripts indicate which ports are involved. For amateur radio operators, this is important for RF measurements. Understanding this helps when using network analyzers.
考试技巧
S parameter subscripts = port or ports at which measurements are made. Think 'S'ubscripts = 'S'ource and 'D'estination ports. S parameter subscripts indicate which ports are involved. Not time, not quality, not frequency order - just ports.
记忆口诀
S parameter subscripts = port or ports at which measurements are made. Think 'S'ubscripts = 'P'orts. S parameter subscripts indicate which ports are involved. Important for RF measurements.
实际应用示例
S parameter subscripts: They represent the port or ports at which measurements are made. For example, S21 means signal from port 1 to port 2. The first number is the output port, the second is the input port. This is what subscripts represent - ports.
错误选项分析
Option B: Incorrect. Relative time between measurements isn't what subscripts represent - subscripts indicate ports. Time isn't the meaning. Option C: Incorrect. Relative quality of data isn't what subscripts represent - subscripts indicate ports. Quality isn't the meaning. Option D: Incorrect. Frequency order of measurements isn't what subscripts represent - subscripts indicate ports. Frequency order isn't the meaning.
知识点
S parameters, Subscripts, Port or ports, Measurements
Verified Content
Question from official FCC Extra Class question pool. Explanation reviewed by licensed amateur radio operators.