Quiz_Chpt4-3_Q - CHAPTER 4 Problem Consider a communication...

Info icon This preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
C HAPTER 4 Problem: Consider a communication system, modeled as y = xC + n , where y is the received signal, x is the input signal and takes values on {–3, –1, +1, +3}, C is a known positive constant used for power control, and n is the additive noise modeled as a Gaussian random variable with zero mean and variance σ 2 . As x takes on 4 values, for every transmission x can carry 2 information bits. Here, the following mapping from two information bits, b 0 b 1 , to an input signal, x , is adopted (see the following figure), 10 Æ –3, 11 Æ –1 01 Æ +1, 00 Æ +3 Upon receiving y , the receiver makes a hard decision on x and recovers the transmitted two information bits. Answer the following question regarding this communication system. 1. When transmitting two information bits ( b 0 b 1 ) = (01), what is the error probability? (a) Q ( C / σ ) (b) 2 Q ( C / σ ) (c) Q (2 C / σ ) (d) 2 Q (2 C / σ )
Image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern