公开(公告)号：US5199108A

公开(公告)日：1993-03-30

申请号：US292494

申请日：1988-12-30

申请人： Richard E. Morgan ,  Nolan D. Self

发明人： Richard E. Morgan ,  Nolan D. Self

IPC分类号： H04B1/04 ,  H04H20/61

CPC分类号： H04H20/61 ,  H04B1/0458

摘要： A radio information system operating at low power transmits in the AM broadcast band. A message to be broadcast is digitized and stored in a random access memory. It is retrieved from the memory, converted to analog form, and used to modulate a carrier signal. The message is continuously repeated, allowing nearby persons with AM radio sets to receive the message. In order to extend the useful range of the information system, an impedance matching circuit with a high-Q inductor is located between the antenna and the output circuitry of the transmitter.

摘要翻译： 以低功率运行的无线电信息系统在AM广播频带中发射。 要广播的消息被数字化并存储在随机存取存储器中。 它从存储器中检索，转换为模拟形式，并用于调制载波信号。 该消息不断重复，允许附近的AM无线电台接收消息。 为了扩展信息系统的有用范围，具有高Q电感的阻抗匹配电路位于天线和发射机的输出电路之间。