This paper presents a robust timing synchronization method for full duplex orthogonal frequency division multiplexing (OFDM) systems based on Long Term Evolution (LTE). The proposed method contains two essential steps: 1) time alignment between the desired signal and self-interference 2) normalized synchronization peak (NSP) index switching. The time alignment is to make the difference in arrival times of the desired signal and the self-interference signal within cyclic prefix (CP) duration of an OFDM symbol, exploiting a time advance, thereby adopting low-complexity, frequency domain self-interference cancellation and decoding. In the second step, to improve the probability of successful time synchronization, a Zadoff-Chu sequence with a different root index is used for the primary synchronization signal at each node. To validate the proposed method with experimental evidence, we implement a full duplex physical layer (PHY) on an FPGA-based software-defined radio (SDR) platform. It is shown that our full duplex OFDM synchronizer is flexible and robust, in a real-world wireless channel, compared to existing synchronization method.
|Title of host publication||2017 IEEE Global Conference on Signal and Information Processing, GlobalSIP 2017 - Proceedings|
|Publisher||Institute of Electrical and Electronics Engineers Inc.|
|Number of pages||5|
|Publication status||Published - 2018 Mar 7|
|Event||5th IEEE Global Conference on Signal and Information Processing, GlobalSIP 2017 - Montreal, Canada|
Duration: 2017 Nov 14 → 2017 Nov 16
|Name||2017 IEEE Global Conference on Signal and Information Processing, GlobalSIP 2017 - Proceedings|
|Other||5th IEEE Global Conference on Signal and Information Processing, GlobalSIP 2017|
|Period||17/11/14 → 17/11/16|
Bibliographical noteFunding Information:
V. CONCLUSIONS We presented a new timing synchronization method for full-duplex communication systems, using the desired and self-interference signals of each user. As proof-of-concept, by implementing the proposed method on our full-duplex SISO/MIMO link prototype, we experimentally verified that the NSP index switching achieved high probability of timing synchronization success. We believe our initial test results provide worthwhile insights for the development of a more viable full-duplex radio. ACKNOWLEDGMENT This work was supported by Institute for Information & Communications Technology Promotion(IITP) grant funded by the Korea government(MSIT) (2015-0-00300, Multiple Access Technique with Ultra-Low Latency and High Efficiency for Tactile Internet Services in IoT Environments).
All Science Journal Classification (ASJC) codes
- Information Systems
- Signal Processing