Host-based Card Emulation with Fixed Card ID
This is (at least with the official API) not possible:
In the first part of the exchange the HCE device will present its UID; HCE devices should be assumed to have a random UID. This means that on every tap, the UID that is presented to the reader will be a randomly generated UID. Because of this, NFC readers should not depend on the UID of HCE devices as a form of authentication or identification.
(http://developer.android.com/guide/topics/connectivity/nfc/hce.html#ProtocolParams)
According to one of the Google developers responsible for HCE:
Sorry, I realize many people wanted this, but it's not possible in the official version. (You could of course do it with some AOSP hacking). The reason is that HCE is designed around background operation. If we allow apps to set the UID, every app possibly wants to set their own UID, and there's no way to resolve the conflict. We hope that with HCE, NFC infrastructure will move to higher levels of the protocol stack to do authentication instead of relying on the UID (which is easily cloned anyway).