Multicarrier Transmission via Gabor Frames: Signal Design and Channel Compensation

A new approach is proposed on the design of pulse-shaped multicarrier systems that are robust to time and frequency selective channels which are known to limit the performance of conventional multicarrier schemes. In contrast to proposed approaches that result in inefficient bandwidth utilization, a tight packing of the subcarriers in the time-frequency domain is considered which renders them linearly dependent (i.e., transmission is achieved via a Gabor frame). System design requires selection of the Gabor frame parameters as well as the introduction of appropriate correlation on the transmitted data in order to allow simple channel compensation and data detection at the receiver. A sub-optimal design solution is proposed, based on an information-theoretic criterion, with the corresponding analysis demonstrating significant gains with respect to conventional multicarrier transmission. Practical detection schemes are also proposed that trade-off complexity versus performance.