LOW POWER RADAR LEVEL GAUGE SYSTEM

摘要

The present invention relates to a radar level gauge system comprising a signal propagation device; a microwave signal source; a microwave signal source controller; a mixer configured to combine a transmit signal from the microwave signal source and a reflection signal from the surface to form an intermediate frequency signal; and processing circuitry coupled to the mixer and configured to determine the filling level based on the intermediate frequency signal.

主权项

1. A radar level gauge system for determining the filling level of a product in a tank, comprising:
a signal propagation device arranged to propagate an electromagnetic transmit signal towards a surface of the product and to return an electromagnetic reflection signal resulting from reflection of the electromagnetic transmit signal at the surface; a microwave signal source coupled to said signal propagation device and controllable to generate said electromagnetic transmit signal; a microwave signal source controller coupled to said microwave signal source and configured to control said microwave signal source to generate said transmit signal in the form of a measurement sweep comprising a time sequence of discrete and mutually different frequency steps defining a bandwidth of said transmit signal; a mixer coupled to said microwave signal source and to said signal propagation device, and configured to combine said transmit signal and said reflection signal to form an intermediate frequency signal; a sampler coupled to said mixer and configured to sample said intermediate frequency signal at a plurality of sampling times during said measurement sweep; and processing circuitry coupled to said mixer and configured to determine said filling level based on said intermediate frequency signal, wherein said microwave signal source controller and said sampler are controllable independently of each other, in such a way that a duration of each of the frequency steps comprised in said measurement sweep can be made different from a sampling time interval between consecutive ones of said sampling times.