look at this document
This chapter provides background on the Interna lWLAN Access Point which runs on-board the IR829 router.
The AP803 works as a standalone access point or with a wireless controller.
The AP803 image is not included in the IR829 IOS bundle.
The AP803 image must be installed separately after obtaining the new AP803 release from Cisco.com.
look here to download the lightweight AP image