1 Introduction
2 System model
2.1 Network setup
2.2 Channel model
3 General power control mechanism in 3GPP LTE-A uplink
3.1 Open-loop power control
3.2 Closed-loop power control
TPC command field in DCI format 0/3/4 | TPC command values [dB] |
---|---|
0 | −1 |
1 | 0 |
2 | 1 |
3 | 3 |
3.3 Power headroom report
3.4 Shortcomings of existing power control schemes in 3GPP LTE-A uplink
4 Proposed uplink power control procedure for 3GPP LTE-A system
4.1 Proposed PHR-PERA scheme
4.2 Adaptive open-loop power control
4.3 PHR and SINR-based closed-loop power control
5 Performance evaluation
5.1 Simulation parameters
Parameter | Value |
---|---|
Carrier frequency | 1.76 GHz |
Bandwidth | 10 MHz |
Number of PRBs | 48 + 2 (control channel) |
Cellular layout of macrocells | Hexagonal grid, 3 sector cells/eNB |
Number of sites | 7 cells (21 sectors) |
Region of interest (ROI) | Center cell (3 sectors) |
Inter-site distance | 500 m |
HeNB deployment model | 5 × 5 grid model |
Number of HeNBs/macrocell | 5 |
Number of MUEs/eNBs | 8 |
Number of FUEs/HeNBs | 3 |
UE maximum transmission power (P
max) | 23 dBm |
Traffic model | Full buffer |
Simulation duration | 30 drops, 500 TTIs |
5.2 Evaluation of the proposed PHR-based uplink power control procedure
5.2.1 Initial parameter setting in conventional open-loop power control
5.2.2 Conventional fractional power control with the proposed PHR-PERA algorithm
Sum throughput | Conventional FPC | Conventional FPC with PHR-PERA | Gain |
---|---|---|---|
MUE sum throughput (Mbps) | 14.07 | 21.1 | 49.9 % |
FUE sum throughput (Mbps) | 143.7 | 150.5 | 4.7 % |
5.2.3 Adaptive open-loop power control with the proposed PHR-PERA scheme
Sum throughput | Conventional FPC with PHR-PERA | Adaptive OL-PC with PHR-PERA | Gain |
---|---|---|---|
MUE sum throughput (Mbps) | 21.1 | 24.74 | 21.9 % |
FUE sum throughput (Mbps) | 150.5 | 157.8 | 4.8 % |