This preview shows pages 1–2. Sign up to view the full content.
This preview has intentionally blurred sections. Sign up to view the full version.View Full Document
Unformatted text preview: ECE 5670 : Digital Communications (Spring 2011) Homework 6 Due March 10 in class Instructor: Salman Avestimehr Office 325 Rhodes Hall 1. At the end of Lecture 10, we considered a simple scheme to estimate the ‘ th wireline channel coefficient h ‘ . (a) For large enough SNR , by how much does the error variance decrease if we increase the SNR by a factor of two? (b) Now suppose we really cannot increase our transmit energy E (the one that we used to learn the channel coefficient) – this could be because of the peak voltage constraints of the power amplifier. But we would really like to get a better estimate than is possible with the constraint of transmit energy E . The engineer thinks about this and comes up with the following idea. We use extra time to learn the channel coefficients. i. Propose a concrete (with as many details as possible) scheme that uses kL time instants to learn the channel coefficients using a total energy of kE with no more energy than E for any particular time instant.for any particular time instant....
View Full Document
This note was uploaded on 10/02/2011 for the course ECE 5670 taught by Professor Scaglione during the Spring '11 term at Cornell University (Engineering School).
- Spring '11