| 摘要 |
<p>A remote radio listenership monitoring system including a digitally tuned scanning receiver (20) disposed in an area adjacent to automobiles (12) carrying radio receivers which radiate intermediate frequency signals (16) which correspond to the stations being received by the radio receivers, the scanning receiver (20) utilizes a narrowed filter scheme to sense the presence of an intermediate signal (16) of predetermined power and rapidly polls a plurality of target frequencies. The system compiles target 'hits' in a local memory device (22) to create a database for that local unit. Periodically, the databases are transferred to a central processing station (26) where individual local unit databases are compiled into a comprehensive report. Communication between the remote local units and the central processing station may be accomplished through a hard wired or cellular link (24). Updates to the system software and new target frequency data are transferred to the remote units by the central processing station.</p> |
