Orthogonal Frequency Division Multiplexing in Wireless Communication Systems

Orthogonal Frequency Division Multiplexing (OFDM) is a multi-carrier modulation technique in which a high-rate data stream is divided into a number of parallel low-rate substreams, each modulating an orthogonal subcarrier. By ensuring orthogonality between closely spaced subcarriers, OFDM achieves high spectral efficiency and resilience to multipath fading typically encountered in mobile and broadband wireless channels. A cyclic prefix inserted between OFDM symbols mitigates intersymbol interference, while channel estimation and equalisation techniques compensate for time dispersion and frequency-selective fading. Standardised in applications such as Wi-Fi, LTE and 5G New Radio, OFDM underpins modern wireless communication systems by supporting high data rates, flexible resource allocation and robust performance in diverse propagation conditions. Key challenges remain, including sensitivity to carrier frequency offset which can induce inter-carrier interference, and the high peak-to-average power ratio demanding efficient power amplifiers. Innovations in adaptive bit and power loading, advanced error-correction coding and multiple-input multiple-output configurations continue to enhance OFDM capacity, reliability and energy efficiency, driving its global significance in broadband access, mobile networks and emerging Internet of Things deployments.

Research from Nature Portfolio

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Research from all publishers

Recent studies in non-Nature journals have advanced OFDM techniques across error control, transform domains and image transmission. A 2023 investigation into Reed–Solomon-coded OFDM in Rayleigh fading channels proposed symbol-level power control strategies to minimise codeword error rate. By combining channel inversion at the transmitter with erasure generation through ordered fading amplitudes at the receiver, the study achieved lower codeword error rates across a range of signal-to-noise ratios per bit, demonstrating the efficacy of joint power allocation and erasure marking for coded OFDM links. Another line of work explored discrete Hartley transform (DHT)-based OFDM systems by introducing a frequency-domain subcarrier diversity receiver. This design exploits coupling between symmetric carriers inherent in the DHT to increase diversity gain, yielding substantial improvements in bit-error rate compared to conventional Fourier-based OFDM without incurring significant complexity. Complementing transform-based enhancements, research on discrete sine transform (DST)-based OFDMA for compressed image transmission has shown that interleaved subcarrier mapping combined with three-dimensional set partitioning in hierarchical trees compression and QPSK modulation can lower minimum SNR requirements to around 18 dB over standard suburban channel models. These findings illustrate the versatility of OFDM in supporting high-efficiency data services, from robust wireless links to bandwidth-constrained multimedia applications.

Orthogonal Frequency Division Multiplexing in Wireless Communication Systems publication trend

The graph below shows the total number of articles in orthogonal frequency division multiplexing in wireless communication systems across all publications each year (not limited to Nature Index journals).

Technical terms

Orthogonality: the condition in which subcarriers are mathematically independent, preventing mutual interference.
Subcarrier: an individual narrowband frequency channel within an OFDM system, each carrying a separate symbol stream.
Cyclic prefix: a repetition of the end of an OFDM symbol appended to its start to mitigate intersymbol interference.
Inter-carrier interference (ICI): distortion caused by loss of subcarrier orthogonality, often due to frequency offset or Doppler shift.
Reed–Solomon coding: an error-correction technique that encodes data into symbols across multiple subcarriers to correct erasures and errors.
Signal-to-noise ratio (SNR): the ratio of signal power to noise power, a key metric for link quality.
Bit error rate (BER): the proportion of incorrectly received bits within a data stream, indicating communication reliability.

References

1. Power Control of Reed–Solomon-Coded OFDM Systems in Rayleigh Fading Channels. Information (2023).
2. Frequency-domain subcarrier diversity receiver for discrete Hartley transform OFDM systems. EURASIP Journal on Wireless Communications and Networking (2019).
3. Performance analysis of wireless compressed-image transmission over DST-based OFDMA systems. EURASIP Journal on Wireless Communications and Networking (2023).