Software-Defined Radio Network Positioning Technology Design. Synchronization Refinement

Positioning accuracy investigation in widespread LTE (Long Term Evolution) and emerging 5G NR (New Radio) wireless communications networks, using Software-Defined Radio (SDR) during experimental verification, is an actual and relevant topic for research and investigations in the last years. Besides employed signal bandwidth and time delay estimation (TDE) precision at the receiver, user equipment (UE) positioning accuracy, using specified by 3GPP observed time difference of arrival (OTDOA), strongly depends on transmitting eNodeB (eNB) time and frequency synchronization. Current investigation is a continuation of SDR LTE network positioning technology design and is devoted to precise eNB SDR testbeds time synchronization. Contribution of this work is an experimentally validated approach, attaining subnanosecond synchronization, using continuous real-time clock refinement of two eNB SDR testbeds, synchronized through precision time protocol (PTP).