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Research Article Intercarrier Interference in OFDM: A General Model for Transmissions in Mobile Environments with Imperfect Synchronization | Hindawi Publishing Corporation EURASIP Journal on Wireless Communications and Networking Volume 2009 Article ID 786040 11 pages doi 2009 786040 Research Article Intercarrier Interference in OFDM A General Model for Transmissions in Mobile Environments with Imperfect Synchronization Martin García and Christian Oberli Department of Electrical Engineering Pontificia Universidad Católica de Chile 7820436 Macul Santiago Chile Correspondence should be addressed to Christian Oberli obe@ Received 2 June 2009 Accepted 16 September 2009 Recommended by Stefan Kaiser Intercarrier Interference ICI is an impairment well known to degrade performance of Orthogonal Frequency Division Multiplexing OFDM transmissions. It arises from carrier frequency offsets CFOs from the Doppler spread due to channel time-variation and to a lesser extent from sampling frequency offsets SFOs . Literature reports several models of ICI due to each kind of impairment. Some studies describe ICI due to two of the three impairments but so far no general model exists to describe the joint effect of all three impairments together. Furthermore most available models involve some level of approximation and the diversity of approaches makes it cumbersome to compare power levels of the different kinds of ICI. In this work we present a general and mathematically exact model for the ICI stemming from the joint effect of the three impairments mentioned. The model allows for a vis-a-vis comparison of signal-to-ICI ratios SIRs caused by each impairment. Our result was validated by simulations. An analysis of ICI in transmissions shows that during steady-state tracking and at speeds below 150 km h SIR due to CFO is typically in the range between 25 dB and 35 dB SIR due to Doppler spread is larger than 25 dB and ICI due to SFO is negligible. Copyright 2009 M. García and C. Oberli. This is an open access article distributed under the Creative Commons Attribution License which permits .