The Google Nexus One has always had a capability to play FM Radio, but Google said they had no plans to implement the necessary software technology to enable the FM Radio. In fact, the similar HTC Desire even has a FM Radio app, so there is no doubt the Nexus One could play FM Radio if made to do so. With that in mind, it looks like people have already begun working on the necessary ROM that will enable the N1 to play FM Radio.
A user named intersectRaven already created a kernal that can be used in ROMs to make FM Radio a reality. The problem is, you cannot download and install the kernal into your N1 and expect it to work, you will have to wait until the kernal is implemented in a ROM first. Basically, a kernal is a necessary component of any ROM, but the user never actually uses or sees the kernal at work, only the ROM developer. However, a developer by the name of Paul O’Brien is already using intersectRaven’s kernal in his own FM Radio ROM that should be available soon. His tweet can be seen below:
Cool, FM radio working in my forthcoming Froyo Sense (r23) port for Nexus One thanks to intersectraven’s kernel!
Read [XDA-Developers Forum]