Hindustan Aeronautics Limited (HAL) is set to upgrade the Indian Air Force’s Tejas Mk1 variants with advanced Software-Defined Radio (SDR) systems, bringing their capabilities in line with the Mk1A models already in production. This enhancement, focusing on indigenously developed SDR-1 and SDR-2 technologies by HAL and the Defence Research and Development Organisation (DRDO), will introduce multi-band, multi-mode communication across V/UHF, L-bands, and SATCOM frequencies, supporting waveforms like Legacy AM/FM, Frequency Hopping voice, Mobile Ad Hoc Networking, and Pulse Address Multiple Access. The systems feature two RF channels, MIL-STD-1553B interfaces, compact ½ ATR form factors, and Software Communications Architecture compliance for seamless upgrades without hardware changes, improving secure data links, real-time situational awareness, and network-centric warfare interoperability. While the Mk1A incorporates Israel’s Elta-supplied B-NET SDR, the upgrades emphasize domestic solutions to reduce foreign dependence, with additional global manufacturers like Thales, BAE Systems, and Elbit Systems noted for similar military-grade SDRs. This move bolsters India’s indigenous defense ecosystem, enhancing aerial combat flexibility and operational efficiency amid evolving threats.