Following the principle of reuse partitioning, two new frequency planning schemes are proposed, the coverage-oriented scheme and the efficiency-oriented scheme, for the cellular system with two-hop fixed relay nodes (FRNs). Compared with the effficiency-oriented scheme, the coverage-oriented scheme has higher reuse distances and is developed with emphasis on the coverage, while compared with the coverage-oriented scheme, the efficiency-oriented scheme has smaller reuse distances and is developed with emphasis on the spectral efficiency. Taking uplink as an example, both simplified analysis and intensive computer simulations are presented to offer comparisons among FRN enhanced systems with the proposed schemes, with a known channel-borrowing based frequency planning scheme and the conventional cellular system without relaying. Studies show that the FRN enhanced system with the coverage-oriented scheme provides the best coverage, while that with the efficiency-oriented scheme offers the highest area spectral efficiency.
The frequency planning for a cellular system enhanced with two-hop fixed relay nodes (FRNs) is investigated. It is assumed that there is no performance-enhancing technique on the base station (BS)-FRN links. Under the assumed condition, two frequency planning schemes are proposed by the principle of reuse partitioning (RP). The frequency planning schemes are compared with the channel-borrowing-based frequency planning scheme and the conventional frequency planning scheme without relaying. Theoretical analysis and simulation results show that the proposed schemes can improve the service quality for mobile terminals close to cell boundaries and provide better performance over the channel-borrowing-based frequency planning. Finally, to fully exploit the potentials of FRN enhanced cellular system, some performance enhancing techniques on BS-FRN links are indispensable.