Cross-layer optimization: Difference between revisions

Revision as of 01:14, 1 March 2016

Revision as of 01:15, 1 March 2016

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== Adapting MAC scheduling based on PHY parameters ==

Communication systems that need to operate over media with non stationary background noise may benefit from having a close coordination between the [[Medium access control|MAC]] layer (which is responsible for scheduling transmissions) and the [[Physical layer|PHY]] layer (which manages actual transmission and reception of data over the media), as for e.g.,

<ref>S. Shabdanov, P. Mitran, C. Rosenberg,

[http://ieeexplore.ieee.org/xpl/login.jsp?tp=&arnumber=6151784&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Farnumber%3D6151784 "Cross-layer optimization in wireless multihop networks ", in IEEE Transactions on Wireless Communications]</ref>

"Cross-layer optimization in wireless multihop networks "] </ref>

<ref>F. Foukalas et al.,

[http://ieeexplore.ieee.org/xpl/login.jsp?tp=&arnumber=6151784&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Farnumber%3D6151784 "Cross-layer design proposals for wireless mobile networks: a survey and taxonomy "]</ref>

In some communications channels (for example, in power lines), noise may be non-stationary and might vary synchronously with the 50 or 60&nbsp;Hz [[AC current]] cycle. In scenarios like this, overall system performance can be improved if the MAC can get information from the PHY regarding when and how the noise level is changing, so that the MAC can schedule transmission during the periods of time in which noise levels are lower.