Measuring radio-frequency impedance
AssigneeU.S. Philips Corporation
InventorsMichael J. Underhill, Peter A. Lewis
Life of this patent
Estimating the term…
Abstract
A method and apparatus for deriving radio-frequency impedance information of an electrical network, for example, an aerial, by using a current converter for inducing a radio-frequency current into the network and a voltage converter for impressing a radio-frequency voltage on the network. By applying radio-frequency signals to the converters, the resultant signals present in the network may be detected by connecting a radio receiver to the network, from which detected signals the impedance may be derived. By directly connecting the radio receiver to the network, the radio-frequency energy applied to the network by the converters may be kept very small.
Claims8
Apparatus for deriving radio-frequency impedance information of an electrical network, comprising a source of radio-frequency signals, a radio receiver, and a transmission path having one end connected to a port of said electrical network and the other end connected to said radio receiver, said transmission path comprising two converters each for injecting a radio-frequency signal and consisting respectively of a current converter arranged for injecting a predetermined radio-frequency current derived from said source in parallel with said port and a voltage converter arranged for injecting a predetermined radio-frequency voltage derived from said source in series both with said port and with said radio receiver for producing resultant signals in said radio receiver from which said radio receiver derives an output indicative of a parameter of the radio-frequency impedance presented to said converters by said network at said port.
A method of deriving radio-frequency impedance information of an electrical network, wherein the method comprises:
- coupling a radio receiver to a port of the network;
- generating two radio-frequency signals consisting respectively of a predetermined radio-frequency current and a predetermined radio-frequency voltage;
- injecting said radio-frequency current in parallel with said port of said network and injecting said radio-frequency voltage in series both with said port and with said radio receiver for producing resultant signals in said radio receiver;
- detecting said resultant signals with said radio receiver;
- and
- deriving, from the detected signals, information of the radio-frequency impedance presented by said network at said port.
Dependencies are inferred from the claim text.