A method for mitigating high intercellular interference in cellular OFDM/TDMA networks operating in time division duplexing (TDD) mode with 100% frequency re-use is proposed. This method employs a busy-tone to sense the channel gain to mitigate high inter-cellular interference scenarios. The busy-tone (known symbol) is broadcasted by the receivers in a special time-slot, then will be received by the transmitters. By comparing the received busytone with a given threshold, the transmitter will determine whether it can transmit data or not. This mechanism is denoted as decentralised time-slot allocation using busy-tone. This is compared with the more traditional centralised time-slot allocation using received interference. In this method, the interference is measured by the receivers. Based on the measured receiver interference, the network controller decides if it can transmit data or not. Numerical results show significant improvements in system throughput from the application of the first method compared to the second, even though the second one requires the network controller and more signalling overhead for interference measurement.
[1]
H. Rohling,et al.
Performance comparison of different multiple access schemes for the downlink of an OFDM communication system
,
1997,
1997 IEEE 47th Vehicular Technology Conference. Technology in Motion.
[2]
P. Godlewski,et al.
Locally centralized dynamic resource allocation algorithm for the UMTS in Manhattan environment
,
1998,
Ninth IEEE International Symposium on Personal, Indoor and Mobile Radio Communications (Cat. No.98TH8361).
[3]
Larry J. Greenstein,et al.
An empirically based path loss model for wireless channels in suburban environments
,
1999,
IEEE J. Sel. Areas Commun..
[4]
Hassan Yaghoobi,et al.
Scalable OFDMA Physical Layer in IEEE 802.16 WirelessMAN
,
2004
.