Orthogonal frequency division multiplexing meaning

In communications and technology contracts and regulatory filings, orthogonal frequency division multiplexing (OFDM) describes a digital modulation method in which data is sent over many closely spaced, mathematically “orthogonal” sub-carriers. By splitting a signal into narrowband channels at different frequencies, OFDM reduces inter-channel interference and copes well with multipath, enabling efficient spectrum use. It is a descriptive technical term rather than a defined legal term; legislation and case law in England & Wales, Scotland, Northern Ireland and Ireland do not generally define it. It is, however, specified in standards (for example ETSI DAB/DAB+, DVB-T/T2; IEEE 802.11 Wi‑Fi; and 3GPP 4G/5G using OFDM/OFDMA), which are often incorporated by reference in contracts, procurement documents, compliance statements and spectrum licences issued by Ofcom (UK) and ComReg (Ireland). Typical legal relevance includes: drafting and interpreting telecommunications and broadcasting agreements; assessing conformity of radio equipment and Wi‑Fi devices; resolving interference and quality-of-service disputes; and analysing standard-essential patent (SEP) and FRAND licensing issues. OFDM is used in DAB digital radio and digital terrestrial television (Freeview/Saorview via DVB-T/T2), Wi‑Fi, broadband wireless and mobile networks. Usage and understanding of the term are broadly consistent across the UK and Ireland.