We demonstrate a coherent OFDM-PON based on a simplified coherent receiver, which exploits a DFB local oscillator without phase/frequency locking. We achieve ultra-narrow channel spacing (Δν = 1.6 GHz) and high-power budget (43 dB/35 dB) for 1.25/10 Gb/s. Introduction Next generation access networks based on WDM-PON can offer higher network capacity, easier network upgrades and more flexibility in network management together with large bandwidth to the customers. In the λ-to-the-user scenario, for example, separate wavelengths are offered directly to single residential-business subscribers. Even though WDM-PON is a promising technology, the problem of its cost-effectiveness is still open