Core Concepts
The core message of this article is to propose efficient algorithms for joint transmit and receive port selection in fluid-MIMO systems in order to maximize the channel capacity.
Abstract
The article presents a new approach for maximizing the channel capacity in fluid-MIMO systems through the selection of antenna ports/positions at both the transmitter and receiver.
Key highlights:
- The authors formulate a binary optimization problem to select the optimal ports that maximize the channel capacity.
- To solve this problem efficiently, they propose a joint convex relaxation (JCR) approach and develop two optimization algorithms with different performance-complexity tradeoffs: JCR&RES (joint convex relaxation and reduced exhaustive search) and JCR&AO (joint convex relaxation and alternating optimization).
- Numerical results show that the proposed algorithms significantly outperform two baseline schemes (random port selection and conventional MIMO) in terms of achieving higher channel capacity.
- The synergy between MIMO and fluid antennas is discussed, highlighting that substantial gains can be attained even when the fluid antenna ports are located very close to each other.
Stats
The channel capacity increases with the number of ports per fluid antenna.
The proposed algorithms remain robust over a wide range of average SNR per receive fluid antenna.
The channel capacity reaches a peak value as the size of fluid antennas (in wavelengths) increases, due to the reduction in spatial correlation.