The devices are based on 100ppb parts released two years ago and, despite now including an oven, measure 7 x 9 x 6.5mm.

The firm is aiming frequency provision in 5G infrastructure, where many mini-basestations will be spread across the landscape, in less-protected locations compared with 3G or 4G basestions – on lamp posts, for example, which will be exposed to more vibration and thermal variation.