High data rate wireless links are an affordable and easily deployable solution to replace or complement fibre. The wide frequency band available at millimetre waves above 100 GHz can support multi-gigabit per second data rate. However, the high attenuation due to rain and humidity poses a substantial obstacle to long-range links. This study describes a wireless system being developed for point-to-point links at D-band (DLINK), above 150 GHz, to enable a full fibre-on-air link with more than 1 km range and unprecedented data rate up to 45 Gb/s. The upper end of the D-band spectrum is used (151.5–174.8 GHz) in full frequency division duplex transmission. The DLINK system consists of a transmitter using a directly modulated resonant tunnelling diode oscillator powered by novel travelling wave tubes. The performance and the small footprint of the front end will make the DLINK system highly competitive to the point-to-point links presently available in the market at frequencies below 100 GHz. The innovative approach and the design are oriented to large-scale productions to satisfy the high data traffic demand of the new 5G infrastructure.