초록 ▼

A receiver receives modulated message signals in non-coherent FSK and coherent 8PSK protocols. A selectively configurable processor demodulates the message signals, and includes a demodulator that derives in-phase and quadrature signals based on the message signals. A phase detector is responsive to

A receiver receives modulated message signals in non-coherent FSK and coherent 8PSK protocols. A selectively configurable processor demodulates the message signals, and includes a demodulator that derives in-phase and quadrature signals based on the message signals. A phase detector is responsive to the in-phase and quadrature signals and delayed in-phase and quadrature signals to derive a phase signal. A selector is responsive to the in-phase and quadrature signals to selectively connect a loop filter between the phase detector and the demodulator. When the selector connects the filter between the phase detector and demodulator, the demodulator is responsive to filtered phase signals to lock onto a frequency of the message signals so that the processor operates as a phase locked loop to demodulate coherent modulated signals. When the selector disconnects the filter from between the phase detector and the demodulator, the demodulator demodulates non-coherent modulated signals and the phase detector supplies a phase signal representing the slope of the phase of the demodulated signal.

대표청구항 ▼

[ What is claimed is:] [1.]1. An industrial process control instrument having a receiver to receive and demodulate message signals that are modulated in either a coherent signal protocol or a non-coherent signal protocol, the receiver including:processor means for receiving message signals and selec

[ What is claimed is:] [1.]1. An industrial process control instrument having a receiver to receive and demodulate message signals that are modulated in either a coherent signal protocol or a non-coherent signal protocol, the receiver including:processor means for receiving message signals and selectively configurable to a first configuration to demodulate message signals modulated in the non-coherent signal protocol to provide phase slope signals representing increasing and decreasing slope of a phase of the message signal, and to a second configuration to demodulate message signals modulated in the coherent signal protocol to provide in-phase and quadrature signals representing a phase relationship of the message signals received by the input;detector means for identifying the protocol of the received message signals; andswitch means responsive to the detector means for switching the processor between its first and second configurations.