PSUN: An OFDM-Pulsed Radar Coexistence Technique with Application to 3.5 GHz LTE

Abstract

This paper proposes Precoded SUbcarrier Nulling (PSUN), an orthogonal frequency-division multiplexing (OFDM) transmission strategy for a wireless communications system that needs to coexist with federal military radars generating pulsed signals in the 3.5 GHz band. This paper considers existence of Environmental Sensing Capability (ESC), a sensing functionality of the 3.5 GHz band coexistence architecture, which is one of the latest suggestions among stakeholders discussing the 3.5 GHz band. Hence, this paper considers impacts of imperfect sensing for a precise analysis. Imperfect sensing occurs due to either a sensing error by an ESC or a parameter change by a radar. This paper provides a framework that analyzes performance of an OFDM system applying PSUN with imperfect sensing. Our results show that PSUN is still effective in suppressing ICI caused by radar interference even with imperfect pulse prediction. As an example application, PSUN enables LTE downlink to support various use cases of 5G in the 3.5 GHz band.

Fault‐tolerant wireless‐optical broadband access network with cluster‐controlled architecture

“…The following methods such as integral linear programming and heuristic approaches should be used in this article. Kim et al 10 proposed strategies OFDM pulsing of 3.5‐GHz LTE radar coexistence. In this paper, details concerning the precoded nullity of the subcompany and an orthogonal frequency division are used for multiplexing transmission.…”

Semi-Blind Post-Equalizer SINR Estimation and Dual CSI Feedback for Radar-Cellular Coexistence

“…Radar waveform optimization approaches using mutual information (MI)-based metrics have been investigated in [12] to mitigate interference to secondary users. In addition, new multicarrier waveforms such as Precoded SUbcarrier Nulled-Orthogonal Frequency Division Multiplexing (PSUN-OFDM) [13], and FREquency SHift (FRESH)-filtered OFDM [14] have been proposed to improve their resilience to pulsed interference. Unfortunately, these waveforms require significant changes to existing radar systems and cellular standards, which makes their implementation infeasible in the near future.…”

5G or Wi-Fi for HA/DR in the 60 GHz Band?

“…The study measured (i) how much performance a Wi-Fi achieves and (ii) how much interference leaks into the radar. In the same 3.5 GHz band, another study assumed Long-Term Evolution (LTE) as the secondary system [10]. The cellular technology based on orthogonal frequency-division multiplexing (OFDM) adopted a larger inter-subcarrier spacing to overcome the pulsed interference from a coexisting radar.…”

“…More technical approaches on inter-technology coexistence were presented [9]- [10] [11]. A spatio-temporal analysis on the military radar-Wi-Fi coexistence in 3.5 GHz band was studied [9].…”