diff --git a/extensions/adsb.sigmf-ext.md b/extensions/adsb.sigmf-ext.md
deleted file mode 100644
index 388a49a..0000000
--- a/extensions/adsb.sigmf-ext.md
+++ /dev/null
@@ -1,28 +0,0 @@
-# ADS-B Extension v1.0.0
-
-The Automatic Dependent Surveillance-Broadcast (`adsb`) namespace extension
-defines dynamic properties of ADS-B signals extending `annotations`.
-
-## 1 Global
-
-`adsb` does not extend [Global](https://github.com/sigmf/SigMF/blob/main/sigmf-spec.md#global-object).
-
-## 2 Captures
-
-`signal` does not extend [Captures](https://github.com/sigmf/SigMF/blob/main/sigmf-spec.md#captures-array).
-
-## 3 Annotations
-
-The following names are specified in the `adsb` namespace and should be used in
-the `annotations` object:
-
-|name|required|type|unit|description|
-|----|--------|----|----|-----------|
-|`downlink_format`|true|int|N/A|Indicates if an ADS-B signal is a Mode S Short (11) or a Mode S Extended (17) signal.|
-|`message_type`|true|int|N/A|Indicates the type of data in a Mode S Extended signal.  The message type code range is from 0 to 31. The type of messages are aircraft identification (1-4), surface position (5-8), airborne position with barometric (9-18), airborne velocities (19), airborne position with GNSS (20-22), testing (23), reserved (24-27, 30), Emergency/Airborne Collision Avoidance System (ACAS) status (28), trajectory change (29), and aircraft operational status (31).  A signal with a Mode S Short downlink format does not contains a message and is represented by 0.
-|`ICA_address`|true|double|N/A|The International Civil Aviation Organization (ICAO) address of the ADS-B signal.|
-|`binary`|true|string|N/A|The binary signal, either 56 bits (Mode S Short) or 112 bits (Mode S Extended).|
-
-## 4 Examples
-
-No `adsb` examples.