#### Description:

This attribute indicates whether the DSBSpecFrame currently represents its lower or upper sideband, or an offset from the local oscillator frequency. When querying the current value, the returned string is always one of `"` usb`"` (for upper sideband), `"` lsb`"` (for lower sideband), or `"` lo`"` (for offset from the local oscillator frequency). When setting a new value, any of the strings `"` lsb`"` , `"` usb`"` , `"` observed`"` , `"` image`"` or `"` lo`"` may be supplied (case insensitive). The `"` observed`"` sideband is which ever sideband (upper or lower) contains the central spectral position given by attribute DSBCentre, and the `"` image`"` sideband is the other sideband. It is the sign of the IF attribute which determines if the observed sideband is the upper or lower sideband. The default value for SideBand is the observed sideband.

Type:

  String.

#### Applicability

##### DSBSpecFrame

All DSBSpecFrames have this attribute.
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