From 872b2dd0afab7ff3e9f09fd7dfc4545d8ec6d015 Mon Sep 17 00:00:00 2001
From: Bastian Bloessl <mail@bastibl.net>
Date: Thu, 12 Oct 2017 16:24:45 +0100
Subject: [PATCH] python frame utilities

---
 python/CMakeLists.txt |  1 +
 python/__init__.py    |  1 +
 python/utils.py       | 52 +++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 54 insertions(+)
 create mode 100644 python/utils.py

diff --git a/python/CMakeLists.txt b/python/CMakeLists.txt
index 1e6bd6d..22a2a83 100644
--- a/python/CMakeLists.txt
+++ b/python/CMakeLists.txt
@@ -29,6 +29,7 @@ endif()
 GR_PYTHON_INSTALL(
     FILES
     __init__.py
+    utils.py
     DESTINATION ${GR_PYTHON_DIR}/ieee802_11
 )
 
diff --git a/python/__init__.py b/python/__init__.py
index 6d4bcb4..90d9535 100644
--- a/python/__init__.py
+++ b/python/__init__.py
@@ -35,6 +35,7 @@ if _RTLD_GLOBAL != 0:
 
 # import swig generated symbols into the test namespace
 from ieee802_11_swig import *
+from utils import *
 
 # import any pure python here
 #
diff --git a/python/utils.py b/python/utils.py
new file mode 100644
index 0000000..0d2c709
--- /dev/null
+++ b/python/utils.py
@@ -0,0 +1,52 @@
+
+def encoding_to_parameters(encoding):
+
+    encodings = [
+        {"bpsc": 1, "cbps":  48, "dbps":  24},
+        {"bpsc": 1, "cbps":  48, "dbps":  36},
+        {"bpsc": 2, "cbps":  96, "dbps":  48},
+        {"bpsc": 2, "cbps":  96, "dbps":  72},
+        {"bpsc": 4, "cbps": 192, "dbps":  96},
+        {"bpsc": 4, "cbps": 192, "dbps": 144},
+        {"bpsc": 6, "cbps": 288, "dbps": 192},
+        {"bpsc": 6, "cbps": 288, "dbps": 216}
+        ]
+
+    enc = encodings[encoding]
+
+    return enc["bpsc"], enc["cbps"], enc["dbps"]
+
+
+def payload_to_symbols(payload, encoding):
+
+    bpsc, cbps, dbps = encoding_to_parameters(encoding)
+
+    # 24 header + 4 crc + payload
+    data_byte = 24 + 4 + payload
+    symbols = int(round((16 + data_byte * 8 + 6) / float(dbps) + 0.5))
+
+    return symbols + 5
+
+
+def mac_payload_to_payload(payload):
+    return payload - 28
+
+
+def payload_to_mac_payload(payload):
+    return payload + 28
+
+
+def payload_to_samples(payload, encoding):
+    return payload_to_symbols(payload, encoding) * 80 + 1
+
+
+def symbols_to_payload(symbols, encoding):
+
+    bpsc, cbps, dbps = encoding_to_parameters(encoding)
+
+
+    bytes = (((symbols - 5) * dbps) - 16 - 6) / 8
+
+    assert(bytes > 28)
+
+    return bytes - 24 - 4