Research Article

Enhancing Radio Access Network Performance over LTE-A for Machine-to-Machine Communications under Massive Access

Table 2

RACH performance for 3GPP-compliant simulation and the proposed solutions.

Evaluation metricsā€‰3GPP compl. sim.PRACH config. index3 picocells + PRACH config. index15 picocells + PRACH config. index3 agg. points (1:1) + PRACH config. index15 agg. points (1:1) + PRACH config. index3 agg. points (1:k) + PRACH config. index15 agg. points (1:k) + PRACH config. index

Access success probability (%)5k100100100100100100100100
10k99.86100100100100100100100
16k82.78100100100100100100100
20k58.90100100100100100100100
25k38.2199.9199.9510099.9299.9199.9199.92
30k26.8697.4498.5399.9497.3997.4197.5197.69

Average access delay (ms)5k28.6125.7025.4925.225.5525.4925.3625.73
10k40.4126.7126.4425.8726.6226.6126.7726.56
16k67.0528.1127.8526.7927.92827.8527.89
20k71.6230.0129.2927.6130.1830.0729.929.91
25k71.7136.0534.3629.4135.7535.9236.0535.64
30k71.2647.8644.3933.4747.7647.6847.5547.27

Average number of preamble transmissions5k1.581.481.461.451.471.471.461.48
10k2.161.531.511.481.521.521.531.52
16k3.461.601.591.531.591.61.591.58
20k3.681.701.671.581.711.711.71.69
25k3.682.021.931.6722.012.021.98
30k3.662.642.461.892.642.632.622.59