Work carried out and results towards Objective 1:
Period 1: The objective described in the DoA aims to develop ultra-wideband transmitter technologies to enable 10Gb/s 5G modem for fixed wireless broadband operating in the sub-6 GHz band. So far, we have successfully developed the concept of a flexible outphasing transmitter employing a unique phase modulator, supporting multiple modulation schemes. We also designed a transmitter prototype which is now sent for fabrication with a 22 nm CMOS technology. According to transistor-level simulations, the power amplifier is capable of operating at 32 GHz, much higher operating frequency than the original sub-6 GHz. The phase modulator design operates only at around 16 GHz, which is still much higher than the original plan. We intend to improve this further in the next prototype. The digital predistortion (DPD) research is also progressing well. There again, we went a step further than the original plan and are investigating the application of artificial neural network (ANN) to devise efficient high-performance DPD for over-the-air combining array transmitters. The initial results are promising with one paper published and more in the pipeline.
Period 2:
Work carried out and results towards Objective 2:
Period 1:The ESRs are recruited onboarded on time despite COVID-related delays and are enrolled in doctoral programs at respective universities. Their research and studies are progressing well. The industrial secondment plan is already implemented with all ESRs having started with their secondments. ESR1 and ESR2 employed by AALTO (Aalto University) are currently spending time at NOKIA (Nokia Bell Labs Belgium) for their industrial secondment, while ESR3 employed by NOKIA has spent some time at TAU (Tampere University). A workshop has also been organized by AALTO on the topic ‘Challenges in 5G Transceiver Design’, which featured several lectures by invited experts including from the industry.
Period 2:
