Integrated Common Radio Resource Management with Spectrum Aggregation Over Non-Contiguous Frequency Bands

Abstract

This paper proposes an Integrated Common Radio Resource Management (iCRRM). The iCRRM performs classic CRRM functionalities jointly with Spectrum Aggregation (SA), being able to switch users between non-contiguous frequency bands. The SA scheduling is obtained with an optimised General Multi-Band Scheduling algorithm with the aim of cell throughput maximisation. In particular, we investigate the dependence of the throughput on the cell coverage distance for the allocation of users over the 2 and 5 GHz bands for a single operator scenario under a constant average Signal to Interference-plusNoise Ratio. For the performed evaluation, the same type of Radio Access Technology is considered for both frequency bands. The operator has the availability of a non-shared 2 GHz band and has access to part (or all) of a shared frequency band at 5 GHz. The performance gain, analysed in terms of data throughput, depends on the channel quality for each user in the considered bands which, in turn, is a function of the path loss, interference, noise, and the distance from the Base Station. An almost constant gain near 30% was obtained with the proposed optimal solution compared to a system where users are first allocated in one of the two bands and later not able to handover between the bands.

Economic trade-off in the optimization of carrier aggregation with enhanced multi-band scheduling in LTE-Advanced scenarios

“…This work proposes an adaptation and update of the integrated CRRM entity proposed in [11] applied to LTE-A. The iCRRM entity implements inter-band carrier aggregation (CA) by performing scheduling between two component carriers (CCs), i.e.…”

“…First, by using an integer programming (IP)-based algorithm, the inter-frequency handovers are achieved in an optimized way, performing the scheduling via the optimal solution of a general multi-band scheduling (GMBS) problem. Additionally, due to the complexity and the impossibility of allocating UEs to more than one CC, in the GMBS algorithm proposed in [11], an enhanced multi-band scheduling (EMBS) algorithm is alternatively incorporated into the iCRRM entity. This EMBS performs the scheduling functionalities instead of the GMBS with significantly reduced complexity while facilitating to allocate UEs to multiple CCs.…”

“…The method to compute the normalized transmitter power required to maintain such average SINR, i.e. the transmitted power for each cell radii so they all have a similar average cell SINR, was described in our previous works [11] and [20] and considered within the simulation framework of this research.…”

“…Figure 14 shows the average supported cell goodput as a function of the cell radius, R, for the number of users supported under the 1% PLR threshold. In this case, the formulation to compute the transmitter power required to guarantee a similar average SINR for different values of the cell radius is the one from [11]. The transmitter power has been normalized so that comparable results between CCs are assured and eNBs from lower cell radius have reduced energy consumption.…”

“…Nevertheless, this adds further scheduling complexity due to the RB pre-organization functionality. In this context, this work addresses LTE-A CA and proposes an updated integrated Common Radio Resource Management (iCRRM), from [11], that performs CC scheduling to satisfy the user's quality of service (QoS) and experience (QoE) requirements while maximizing spectral efficiency. Two inter-band CA, band 7 (2.6 GHz) and band 20 (800 MHz), are considered.…”