The CEOs of satellite radio firms Sirius Satellite Radio [SIRI] and XM Satellite Radio [XMSR] said that their jointly funded efforts to develop interoperable receivers need “significant” additional work that may not be completed for two or three years, they told attendees during a panel discussion at SATELLITE 2003 Tuesday.

The Federal Communications Commission is requiring the two companies to develop interoperable units, but the agency did not set a deadline, said Joseph Clayton, Sirius’ president and CEO.

Progress on the effort previously was slowed to give Sirius additional time to work with its chipsets, but those technical issues subsequently have been resolved to allow the collaboration to proceed, XM President and CEO Hugh Panero said.