Filter

Description

The class Filter describes the different types of filters that process the signal in the stages of the instrument components of an OBS.

Superclass

None

Subclasses

PolesZeros
FIR
- Analog
Coefficients
- ADConversion
- Digital
Response List

Relationships

Is nested in a Stage

Attributes

Name	Type	Required	Default	Equivalent StationXML	Remarks
type	string	Y	None	N/A	Possible values: “PolesZeros”, “FIR”, “Coefficients”, “Analog”, “Digital”, “ADConversion”
offset	number	Y	None	Decimation.Offset	If delay is not present in the corresponding Stage, it will be set to offset/input_sample_rate

Depending on the type, other attributes will be required

JSON schema

https://www.gitlab.com/resif/obsinfo/-/tree/master/obsinfo/data/schemas/filter.schema.json

https://www.gitlab.com/resif/obsinfo/-/tree/master/obsinfo/data/schemas/definitions.schema.json

Example

This is the filter information file https://www.gitlab.com/resif/obsinfo/-/tree/master/obsinfo/_examples/Information_Files/instrumentation/dataloggers/responses/FIR/CirrusLogic_CS5322_FIR3.filter.yaml , which specifies a “FIR”-type filter.

---
format_version: "0.110"
revision:
   date: "2017-11-30"
   authors:
       -   $ref: "authors/Wayne_Crawford.author.yaml#author"

notes: ["101 coefficients, linear phase filter"]

filter:
   type: "FIR"
   symmetry: "NONE"
   offset: 50
   coefficients:
       - -3.09982E-6
       - -2.94483E-5
       - -9.8002E-5
       - -1.62383E-4
       - -1.00029E-4
       - 1.20655E-4
       - 2.61935E-4
       - 2.52755E-5
       - -4.10488E-4
       - -3.66852E-4
       - 3.7627E-4
       - 8.54597E-4
       - -3.05213E-5
       - -0.00127677
         ...
       - 1.20655E-4
       - -1.00029E-4
       - -1.62383E-4
       - -9.8002E-5
       - -2.94483E-5
       - -3.09982E-6