CHICAGO (AP) ¿ Telular Corp. said Wednesday that Arbitron Inc. has chosen its fixed cellular terminals to collect audience ratings from people without landline phones. Arbitron seeks to increase the participation of youth and members of ethnic groups who only use cell phones. Telular said its terminals connect with Arbitron's Portable People Meter to transmit audience measurement data over cellular networks. The Portable People Meter is a cell-phone size device worn by survey participants that tracks where and when they watch TV, listen to radio and interact with other forms of media. The device detects inaudible codes embedded in content being watched or heard. The codes are extracted after it's placed in a docking station, and sent to a central computer but using phone lines. Chicago-based Telular's terminals let Arbitron use the device even in households that don't have landlines. Columbia, Md.-based Arbitron measures network and local market radio audiences. Telular's products provide remote access for voice and data. Shares of Telular fell 8 cents to $1.60 in midday trading, while Arbitron rose 11 cents to $13.14.