Signal Modulation, Transmitters and Receivers

Write 400–600 words that respond to the following questions with your thoughts, ideas, and comments. Be substantive and clear, and use examples to reinforce your ideas.

As you know, the voice frequencies of modulation techniques for electrical communication systems are up to 15KHz. If you were to design a communication system for voice frequencies, explain which modulation technique you would use for the following cases: 

• Very high Immunity to noise and interference is important
• Narrow signal bandwidth is important, 
• Simple and a cheap electrical receiver is importance. 

In your opinion, which technique is the most expensive and why?