Simrad 38 kHz CHIRP add-on software

 

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Due to advanced matched filtering techniques you can correlate the returned signal with what you sent out, and the result is improved range resolution of single targets. The improved range resolution is obtained when you have targets that are in comparable size.

When you have very weak targets in the near vicinity of strong ones, such as small fish close to bottom, you might want to use a different pulse shape. A dolphin’s click is shorter, but still spans over a large bandwidth and might be better suited for such environments. The ES80 has this capability and, as the SW continues to be developed, new functions would be available.

Wideband Echosounders

The ESs have wideband capabilities. That means that you can transmit a signal that varies in frequency across the transmission. The most common way to operate the sounder is to use linear FM, or chirp. In an ES80 chirp transmission you utilize the effective frequency band of your transducer, starting low and continuing higher until you reach the frequency where the transducer efficiency drops off. Due to advanced matched filtering techniques you can correlate the returned signal with what you sent out, and the result is improved range resolution of single targets. The improved range resolution is obtained when you have targets that are in comparable size. When you have very weak targets in the near vicinity of strong ones, such as small fish close to bottom, you might want to use a different pulse shape. A dolphin’s click is shorter, but still spans over a large bandwidth and might be better suited for such environments. The ES80 has this capability and, as the SW continues to be developed, new functions would be available.