Noise Coupling Path Analysis for RF Interference Caused by LCD Noise Modulation


RF interference caused by liquid crystal display (LCD) noise modulation in a mobile phone was investigated and its noise coupling path was demonstrated. In the frequency division duplex communications, mobile phones can send (uplink) and receive (downlink) at the same time. When an antenna transmits high power signal, the baseband noise from an LCD panel is modulated into an RF band and causes interference in a receiving antenna. A noise coupling path between an antenna and a display driver IC, which drives the LCD panel, was experimentally demonstrate. In addition, a simple noise source model was proposed to represent modulation mechanism. A network analysis with the modulation model showed good correlation with the measured spectra of the modulated noise in a receiving antenna.

Meeting Name

2016 IEEE International Symposium on Electromagnetic Compatibility, EMC 2016 (2016: Jul. 25-29, Ottawa, Canada)


Electrical and Computer Engineering

Research Center/Lab(s)

Center for High Performance Computing Research

Second Research Center/Lab

Electromagnetic Compatibility (EMC) Laboratory

Keywords and Phrases

Antennas; Cellular telephones; Electromagnetic compatibility; Mobile phones; Modulation; Receiving antennas; Regression analysis; Telephone sets; Display driver ic; Frequency-division duplexes; Good correlations; Liquid crystal display(LCD); Modulation models; Noise coupling; Noise source models; RF interference; Liquid crystal displays

International Standard Book Number (ISBN)


International Standard Serial Number (ISSN)


Document Type

Article - Conference proceedings

Document Version


File Type





© 2016 Institute of Electrical and Electronics Engineers (IEEE), All rights reserved.

Publication Date

01 Sep 2016