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| Method | Main characteristics | Advantages | Drawbacks | Validity |
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| Frequency domain compensation schemes |
| Modulation and coding-based schemes | Based on pilot carriers and training sequences. Evaluated by matrix inversion and compensated by variable modulation and coding schemes [10–21] | Applicable adaptive schemes with large performance range.
Low complexity system through IFFT/FFT implementation | Low BER performance at high bit constellation and large computational data from matrix inversion | Adaptive MCS guarantee VANET performance |
| Interference cancellation-based schemes | Based on pilot-aided iterative equalization schemes that exclude IFFT/FFT operation [22–38] | Improved Doppler shift (DS) compensation and low computational complexity by avoiding matrix inversion | Requiring large processing area and power to address iterative operation | Low BER limits application in high mobility VANETs |
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| Time domain compensation schemes |
| Autocorrelation-based schemes | Based on channel autocorrelation function (ACF) to extract received signal compression/expansion as a measure of Doppler spread [39–47] | Simplistic in implementation by avoiding pilot sequences | Low BER performance under linear detection algorithms | Unattractive in VANET application in linear detection schemes |
| Time-partitioning-based schemes | Factor DS degradation into time- and frequency-dispersive components and providing block structured algorithms to deliver solutions block-by-block [48–62] | Achieving high diversity gain resulting in DS reduction with high BER performance | Decision on the type of algorithm imposes extra complexity | A window for choice between the blocks supports VANET application |
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| Space domain compensation schemes |
| Diversity combining-based schemes | Providing high diversity orders to cancel ICI in high mobility scenarios. The large OFDM symbol duration eliminates ISI but simultaneously increases sensitivity to ICI [63–73]. | High BER performance even under oscillator instability frequency offsets and DS | Challenges of ICI/ISI tradeoff constrain model design | Optimum ICI/ISI tradeoff will guarantee efficient application in VANETs |
| Beamforming-based schemes | BER performance based on spatial dimension. Accuracy in angle of arrival (AOA) is key to optimum beamforming [74–81]. | Beamforming increases directional gain with increased BER performance | Rapid variation in AOA undermines BER performance | Efficient application in VANETs will depend on successful tracking of AOA |
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