NC-OFDM Cognitive Radio Optimal Pilot Placement for the LS Estimator

A theoretical contradiction between the areas of the optimal pilot-pattern design and the optimal power loading algorithms has been found to exist for proposed Non-Contiguous Orthogonal Frequency-Division Multiplexing (NCOFDM) Cognitive Radio (CR) systems. It has been found that the proposed, optimal pilot-patterns specify that the Secondary User (SU) should convert the two sub-channels adjacent to a Primary User (PU) to pilot sub-channels in order to ensure the lowest estimator Mean Squared Error (MSE) attainable. This algorithm has been found to contradict with the optimal power loading algorithm for CR systems should the Pilot-to-Data Power Ratio (PDPR) be greater than unity.

Provided by: IARIA Topic: Mobility Date Added: Apr 2012 Format: PDF

Find By Topic