Energy-minimizing bit allocation for powerline OFDM with multiple delay constraints

Optimal Bit Allocation Under Multiple Rate Constraints

Rate-optimized power allocation for OFDM transmission with multiple DF/regenerative relays and individual power constraints

Abstract—We consider an OFDM (orthogonal frequency division multiplexing) point to point transmission scheme improved by means of multiple relays. For each carrier, symbols sent by the source during a first time slot may be retransmitted during a second time slot by the relays, which are assumed to be of the DF (Decode-and-Forward) type. For each relayed carrier the destination implements maxim...

Multiuser OFDM with adaptive subcarrier, bit, and power allocation

Multiuser orthogonal frequency division multiplexing (OFDM) with adaptive multiuser subcarrier allocation and adaptive modulation is considered. Assuming knowledge of the instantaneous channel gains for all users, we propose a multiuser OFDM subcarrier, bit, and power allocation algorithm to minimize the total transmit power. This is done by assigning each user a set of subcarriers and by deter...

Superposition Coding Scheme for Subcarrier & Bit Allocation in OFDM System

Orthogonal Frequency Division Multiple Access (OFDMA) refers to aradio transmission technique based on dividing the frequency channelinto narrowband sub-channels. In this dissertation studied that margin adaptive superposition coding (MA-SC) algorithm and rate adaptive superposition coding (RA-SC) algorithm, where at most two users can share each subcarrier as compared to MA and RA algorithm, w...

Adaptive Subcarrier Allocation and Bit Loading for Multiuser OFDM Systems

This paper proposes a new algorithm of adaptive subcarrier allocation and bit loading for simultaneous voice and data transmission in multiuser OFDM systems. The algorithm dynamically assigns the number of subcarriers and bits/per symbol on each subcarrier for each user in a single cell. To cope with the stringent delay requirement of voice service, the subcarriers with low channel gains are as...