diff --git a/subworkflow/ndppp_prep_cal.cwl b/subworkflow/ndppp_prep_cal.cwl
index d06e9e6551c7fb68f893ece3ac321e30be9733f5..89961f05d01d4986aa96b0d011386555369b8206 100644
--- a/subworkflow/ndppp_prep_cal.cwl
+++ b/subworkflow/ndppp_prep_cal.cwl
@@ -42,7 +42,7 @@ inputs:
     'sbg:x': 2021.81787109375
     'sbg:y': -352.4759216308594
   - id: freqresolution
-    type: string
+    type: int
     'sbg:x': 1999.5889892578125
     'sbg:y': 170.7563934326172
 outputs:
@@ -238,4 +238,4 @@ steps:
 requirements:
   - class: SubworkflowFeatureRequirement
   - class: StepInputExpressionRequirement
-  - class: InlineJavascriptRequirement
\ No newline at end of file
+  - class: InlineJavascriptRequirement