| 摘要 |
A level gauge using microwaves to determine a distance to a surface of a product in a tank, wherein a measurement signal comprises a first frequency sweep, and a second frequency sweep, and a mixer is arranged to mix the measurement signal with an echo signal to form a first IF signal based on the first frequency sweep, and a second IF signal based on the second frequency sweep. Processing circuitry is adapted to sample the first IF signal and the second IF signal, to form a combined sample vector including samples from each tank signal, and to determine the distance based on the combined sample vector. By combining the samples from two (or more) different sweeps, the number of samples and the bandwidth can both be increased, thus maintaining the range L. However, as the samples are obtained from two separate sweeps, the sweep time for each individual sweep does not need to be increased, and the average power consumption can be maintained.
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