Millimetre-wave transceivers are an important ingredient in future wireless radio access networks, especially in the context of fully digital massive MIMO communications, which offer full and flexible beam control. Such infrastructure supports the realization of high capacity networks as sought in 6G systems. However, the realization of energy-efficient millimetre-wave transceivers is extremely challenging requiring new circuit architectures and communication techniques that jointly address power consumption and form factor limitations. Building on previous and current UKRI funded research carried out in the FARAD and DD-mmMaMi projects, this project proposes applying a range of techniques based on direct millimetre-wave synthesis and acquisition, which substantially reduce transmit power consumption and receiver complexity. The techniques are particularly relevant to creating large scale antenna systems for millimetre-wave massive MIMO with full digital control. The techniques are generally applicable to solutions from 30 GHz to 300 GHz, which represent the frequency ranges that the project wishes to address.