"The continuous growth of Internet traffic pushes hard for a cost and energy efficient upgrade of the bit rates in short reach Ethernet, next generation passive optical networks and inter data center links. The goal of this project is to identify and demonstrate cost and power efficient modulation formats for these scenarios. Preferred candidates are formats with high spectral efficiency, intensity modulation, and direct detection. The proposal looks into carrierless amplitude and phase (CAP) modulation, partial response signaling, and optical orthogonal frequency division multiplexing (OFDM). Optical OFDM leveraging advanced digital signal processing has shown great resilience to linear system effects such as fiber dispersion. CAP and partial response are emerging formats that potentially have lower cost and lower power consumption due to an analogue implementation, but have not yet been investigated for optical transmission in very great detail.The major objectives of this project include a theoretical analysis and fair comparison of the different formats on aspects of optical power budget, cost, and power dissipation to identify the optimum formats for the relevant applications; the digital implementation of one or two variants and measurements in the relevant scenarios, and the analogue implementation of CAP and/or partial response optical links. The theoretical work will be based on numerical simulation with input on the component costs from the host. The experimental work is based on the high speed digital/analogue equipment, the test setup, and related hands-on training provided by the host - ADVA Optical Networking.The project is strongly exposed to industry and involves inter-sector mobility, which enables the fellow to generate impact to a wide scope by implementing a number of world first high speed optical links with great commercialization potential, as well as to develop new skills/competencies through flexible training offered by the host."