Full-duplex filtering forwarding relay structure and discrete frequency domain response design method thereof

Abstract

The invention discloses a relay structure of a digital full-duplex filtering forward (FF-FD) system and an optimal design method of the discrete frequency domain response. The relay structure comprises a down-converter, a front-end cascaded VVA, a baseband digital filter, a back-end cascaded VGA, an upper-converter and an amplification module; the design method disclosed by the invention comprisesthe following steps: constructing a relay DFR optimization problem under the digital baseband based on the FF-FD system, thereby finding the optimal relay discrete frequency domain response by satisfying the sending power limitation; directly acquiring the optimal relay DFR coefficient when the channel is the frequency unselective channel; converting into a convex optimization problem for power distribution according to the situation whether the CSI is existent at the sending end when the channel is the frequency selective channel, and effectively solving the optimal relay DFR coefficient; further obtaining the suboptimal relay DFR coefficient, thereby reducing the computation complexity. By using the method disclosed by the invention, the availability of the FF-FD system can be enhancedso as to acquire the system performance superior to the existing AF-FD; and meanwhile, the system complexity and the computation complexity are reduced, and the achievable rate of the system is maximized.

Description

technical field [0001] The invention belongs to the field of wireless communication, relates to a wireless relay communication technology, in particular to a relay structure of a digital full-duplex filter forwarding system and an optimal design method for a discrete frequency domain response thereof. Background technique [0002] Relay communication technology can expand communication range, enhance link quality, and improve spectrum efficiency, so it has been widely researched and applied at present. Traditional relays usually work in half-duplex mode, requiring two orthogonal time-frequency resources to transmit a single signal. Different from the half-duplex mode, the full-duplex technology can transmit and receive data at the same frequency at the same time, and theoretically can double the spectrum efficiency, so it is considered to be a key technology for future wireless networks. In practice, the transmitting antenna of the full-duplex system will cause interference...

AI Technical Summary

Problems solved by technology

Although the pure analog system can eliminate the influence of quantization noise, the design of the filtering structure is too complicated, the flexibility is low, and it is difficult to adjust and optimize dynamically under the time-varying channel; Nearly continuous sampling points are required to achieve optimal performance, and it is difficult to directly extend to the digital domain, resulting in high computational complexity and seriously reducing the availability of the system

Images