Change in libosmocore[master]: conv_codes_gsm: Cosmetic improvements

21 Nov 2022

laforge has uploaded this change for review. (
https://gerrit.osmocom.org/c/libosmocore/+/30261 )


Change subject: conv_codes_gsm: Cosmetic improvements
......................................................................

conv_codes_gsm: Cosmetic improvements

* Fix mixed tab/space indent
* Switch from 05.03 to 45.003
* give the 3GPP spec / section for each code
* make the "magic number" of input bits to the convolutional code
  match the spec.  The code always subtracts any known-zero tail bits
  as this improves decoding.

Change-Id: I7cc6056114f997b5d4febf612ecd347b2d6d69b1
---
M utils/conv_codes_gsm.py
1 file changed, 41 insertions(+), 41 deletions(-)



  git pull ssh://gerrit.osmocom.org:29418/libosmocore refs/changes/61/30261/1

diff --git a/utils/conv_codes_gsm.py b/utils/conv_codes_gsm.py
index 42f340b..cee5efc 100644
--- a/utils/conv_codes_gsm.py
+++ b/utils/conv_codes_gsm.py
@@ -4,7 +4,7 @@
 from conv_gen import ConvolutionalCode
 from conv_gen import poly
 
-# Polynomials according to 3GPP TS 05.03 Annex B
+# Polynomials according to 3GPP TS 45.003 Annex B
 G0 = poly(0, 3, 4)
 G1 = poly(0, 1, 3, 4)
 G2 = poly(0, 2, 4)
@@ -29,9 +29,9 @@
 
 # Convolutional code definitions
 conv_codes = [
-	# xCCH definition
+	# xCCH definition, 3GPP TS 45.003 Section 4.1
 	ConvolutionalCode(
-		224,
+		228 - 4, # 4 tail bits are known to be zero
 		shared_polys["xcch"],
 		name = "xcch",
 		description = [
@@ -42,7 +42,7 @@
 		]
 	),
 
-	# RACH definition
+	# RACH definition, 3GPP TS 45.003 Section 4.6.1
 	ConvolutionalCode(
 		14,
 		shared_polys["xcch"],
@@ -50,7 +50,7 @@
 		description = ["RACH convolutional code"]
 	),
 
-        # Extended RACH definition from 3GPP TS 45.003 §5.3.2
+	# Extended RACH definition, 3GPP TS 45.003 Section 5.3.2
 	ConvolutionalCode(
 		17,
 		shared_polys["xcch"],
@@ -59,7 +59,7 @@
 		description = ["Extended RACH (11 bit) convolutional code"]
 	),
 
-	# SCH definition
+	# SCH definition, 3GPP TS 45.003 Section 4.7
 	ConvolutionalCode(
 		35,
 		shared_polys["xcch"],
@@ -67,9 +67,9 @@
 		description = ["SCH convolutional code"]
 	),
 
-	# CS2 definition
+	# CS2 definition, 3GPP TS 45.003 Section 5.1.2
 	ConvolutionalCode(
-		290,
+		294 - 4, # 4 tail bits are known to be zero
 		shared_polys["xcch"],
 		puncture = [
 			 15,  19,  23,  27,  31,  35,  43,  47,  51,  55,  59,  63,  67,  71,
@@ -91,9 +91,9 @@
 		]
 	),
 
-	# CS3 definition
+	# CS3 definition. 3GPP TS 45.003 Section 5.1.3
 	ConvolutionalCode(
-		334,
+		338 - 4, # 4 tail bits are known to be zero
 		shared_polys["xcch"],
 		puncture = [
 			 15,  17,  21,  23,  27,  29,  33,  35,  39,  41,  45,  47,  51,  53,
@@ -123,7 +123,7 @@
 
 	# CS2 definition (non-punctured)
 	ConvolutionalCode(
-		290,
+		294 - 4, # 4 tail bits are known to be zero
 		shared_polys["xcch"],
 		name = "cs2_np",
 		description = [
@@ -135,7 +135,7 @@
 
 	# CS3 definition (non-punctured)
 	ConvolutionalCode(
-		334,
+		338 - 4, # 4 tail bits are known to be zero
 		shared_polys["xcch"],
 		name = "cs3_np",
 		description = [
@@ -377,17 +377,17 @@
 		]
 	),
 
-	# TCH_FR definition
+	# TCH_FR definition, 3GPP TS 45.003 Section 3.1.2
 	ConvolutionalCode(
-		185,
+		189 - 4, # 4 tail bits are known to be zero
 		shared_polys["xcch"],
 		name = "tch_fr",
 		description = ["TCH/F convolutional code"]
 	),
 
-	# TCH_HR definition
+	# TCH_HR definition, 3GPP TS 45.003 Section 3.2
 	ConvolutionalCode(
-		98,
+		98 - 6, # 6 tail bits are known to be zero
 		[
 			( G4, 1 ),
 			( G5, 1 ),
@@ -522,7 +522,7 @@
 		description = ["TCH/AHS 4.75 kbits convolutional code"]
 	),
 
-	# TCH_AXS SID UPDATE definition
+	# TCH_AXS SID UPDATE definition, 3GPP TS 45.003 Section 3.9.1 + 3.10.1
 	ConvolutionalCode(
 		49,
 		[
@@ -541,7 +541,7 @@
 		]
 	),
 
-	# EDGE MCS1_DL_HDR definition
+	# EDGE MCS1_DL_HDR definition, 3GPP TS 45.003 Section 5.1.5.1.3
 	ConvolutionalCode(
 		36,
 		shared_polys["mcs"],
@@ -556,7 +556,7 @@
 		]
 	),
 
-	# EDGE MCS1_UL_HDR definition
+	# EDGE MCS1_UL_HDR definition, 3GPP TS 45.003 Section 5.1.5.2.2
 	ConvolutionalCode(
 		39,
 		shared_polys["mcs"],
@@ -571,9 +571,9 @@
 		]
 	),
 
-	# EDGE MCS1 definition
+	# EDGE MCS1 definition, 3GPP TS 45.003 Section 5.1.5.1.4
 	ConvolutionalCode(
-		190,
+		190 - 6, # 6 tail bits are known to be zero
 		shared_polys["mcs"],
 		name = "mcs1",
 		description = [
@@ -585,9 +585,9 @@
 		]
 	),
 
-	# EDGE MCS2 definition
+	# EDGE MCS2 definition, 3GPP TS 45.003 Section 5.1.6.1.4
 	ConvolutionalCode(
-		238,
+		238 - 6, # 6 tail bits are known to be zero
 		shared_polys["mcs"],
 		name = "mcs2",
 		description = [
@@ -599,9 +599,9 @@
 		]
 	),
 
-	# EDGE MCS3 definition
+	# EDGE MCS3 definition, 3GPP TS 45.003 Section 5.1.7.1.4
 	ConvolutionalCode(
-		310,
+		316 - 6, # 6 tail bits are known to be zero
 		shared_polys["mcs"],
 		name = "mcs3",
 		description = [
@@ -613,9 +613,9 @@
 		]
 	),
 
-	# EDGE MCS4 definition
+	# EDGE MCS4 definition, 3GPP TS 45.003 Section 5.1.8.1.4
 	ConvolutionalCode(
-		366,
+		372 - 6, # 6 tail bits are known to be zero
 		shared_polys["mcs"],
 		name = "mcs4",
 		description = [
@@ -627,7 +627,7 @@
 		]
 	),
 
-	# EDGE MCS5_DL_HDR definition
+	# EDGE MCS5_DL_HDR definition, 3GPP TS 45.003 Section 5.1.9.1.3
 	ConvolutionalCode(
 		33,
 		shared_polys["mcs"],
@@ -642,7 +642,7 @@
 		]
 	),
 
-	# EDGE MCS5_UL_HDR definition
+	# EDGE MCS5_UL_HDR definition, 3GPP TS 45.003 Section 5.1.9.2.3
 	ConvolutionalCode(
 		45,
 		shared_polys["mcs"],
@@ -657,9 +657,9 @@
 		]
 	),
 
-	# EDGE MCS5 definition
+	# EDGE MCS5 definition, 3GPP TS 45.003 Section 5.1.9.1.4
 	ConvolutionalCode(
-		462,
+		468 - 6, # 6 tail bits are known to be zero
 		shared_polys["mcs"],
 		name = "mcs5",
 		description = [
@@ -671,9 +671,9 @@
 		]
 	),
 
-	# EDGE MCS6 definition
+	# EDGE MCS6 definition, 3GPP TS 45.003 Section 5.1.10.1.4
 	ConvolutionalCode(
-		606,
+		612 - 6, # 6 tail bits are known to be zero
 		shared_polys["mcs"],
 		name = "mcs6",
 		description = [
@@ -685,7 +685,7 @@
 		]
 	),
 
-	# EDGE MCS7_DL_HDR definition
+	# EDGE MCS7_DL_HDR definition, 3GPP TS 45.003 Section 5.1.11.1.3
 	ConvolutionalCode(
 		45,
 		shared_polys["mcs"],
@@ -700,7 +700,7 @@
 		]
 	),
 
-	# EDGE MCS7_UL_HDR definition
+	# EDGE MCS7_UL_HDR definition, 3GPP TS 45.003 Section 5.1.11.2.3
 	ConvolutionalCode(
 		54,
 		shared_polys["mcs"],
@@ -715,9 +715,9 @@
 		]
 	),
 
-	# EDGE MCS7 definition
+	# EDGE MCS7 definition, 3GPP TS 45.003 Section 5.1.11.1.4
 	ConvolutionalCode(
-		462,
+		468 - 6, # 6 tail bits are known to be zero
 		shared_polys["mcs"],
 		name = "mcs7",
 		description = [
@@ -729,9 +729,9 @@
 		]
 	),
 
-	# EDGE MCS8 definition
+	# EDGE MCS8 definition, 3GPP TS 45.003 Section 5.1.12.1.4
 	ConvolutionalCode(
-		558,
+		564 - 6, # 6 tail bits are known to be zero
 		shared_polys["mcs"],
 		name = "mcs8",
 		description = [
@@ -743,9 +743,9 @@
 		]
 	),
 
-	# EDGE MCS9 definition
+	# EDGE MCS9 definition, 3GPP TS 45.003 Section 5.1.13.1.4
 	ConvolutionalCode(
-		606,
+		612 - 6, # 6 tail bits are known to be zero
 		shared_polys["mcs"],
 		name = "mcs9",
 		description = [

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Gerrit-Project: libosmocore
Gerrit-Branch: master
Gerrit-Change-Id: I7cc6056114f997b5d4febf612ecd347b2d6d69b1
Gerrit-Change-Number: 30261
Gerrit-PatchSet: 1
Gerrit-Owner: laforge &lt;laforge(a)osmocom.org&gt;
Gerrit-MessageType: newchange



    

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Change in libosmocore[master]: conv_codes_gsm: Cosmetic improvements