Knowledge (XXG)

Time-assignment speech interpolation

Source 📝

89:. Clipping or loss of speech would occur for all conversations that needed to be assigned to an available idle channel and in practice lasted at least 17 ms whilst information required to re-connect both parties was signalled by the TASI control circuits. An additional freezeout period lasting between 0 and 500 ms would depend on the instantaneous loading of voice circuits. In actual use, these delays presented few problems in typical conversations. 203: 97:
for a similar phenomenon in telecommunications. Another potential issue was ensuring that non-voice type circuits (e.g. Music or radio type circuits where pauses would occur infrequently) were not routed via TASI speech channels since these could seriously degrade the level of service where callers
65:
TASI takes advantage of the fact that in typical person-person conversation, speech in a single direction occurs for approximately 40% of the time, the remaining time being occupied with pauses and/or silence. Statistical analysis demonstrated that for an average voice channel usage of 40%, over 74
92:
One of the issues with using this type of technology was that the users listening on an idled channel can sometimes hear the conversation that has been switched onto it. Generally the sound heard was of very low volume and individual words are not distinguishable. See also
207: 85:
has stopped speaking. When the original user resumes speaking, that user would, in turn, be switched to any channel that happened to be idle. The speech detector function is called
70:
speech circuits thereby doubling potential revenue for a small capital outlay relative to a highly expensive cable. e.g. £12.5 million (£263 million as of 2014) cost of the
192: 54: 127: 159: 32: 218: 212: 43: 67: 47: 82: 86: 245: 188: 134: 20: 167: 239: 78: 222: 228: 107: 94: 39: 98:
would encounter frequent clipped speech and breaks in the conversation.
71: 197: Multihop time assigned speech interpolation, 1991 (TASI) 57:
included TASI as a feature, not as distinct hardware.
16:
Technique to increase capacity of analog phone cables
66:
speech conversations could be handled using 37 full
46:. It was one of their first applications requiring 77:TASI worked by switching additional users onto any 42:in the early 1960s to increase the capacity of 35:links to increase voice transmission capacity. 31:) was an analog technique used on certain long 8: 128:"Overall Characteristics of a TASI system" 55:digital circuit multiplication equipment 119: 81:temporarily idled because an original 74:cable on which TASI was implemented. 7: 133:. September 19, 1961. Archived from 25:time-assignment speech interpolation 14: 206: This article incorporates 201: 219:General Services Administration 44:transatlantic telephone cables 1: 262: 87:voice activity detection 214:Federal Standard 1037C 208:public domain material 227: (in support of 38:TASI was invented by 48:electronic switching 140:on October 14, 2014 50:of voice circuits. 170:on 15 October 2014 21:telecommunications 253: 232: 226: 221:. Archived from 205: 204: 196: 195: 191: 180: 179: 177: 175: 166:. Archived from 156: 150: 149: 147: 145: 139: 132: 124: 261: 260: 256: 255: 254: 252: 251: 250: 236: 235: 211: 202: 200: 193: 187: 184: 183: 173: 171: 164:Secret Scotland 158: 157: 153: 143: 141: 137: 130: 126: 125: 121: 116: 104: 63: 17: 12: 11: 5: 259: 257: 249: 248: 238: 237: 234: 233: 225:on 2022-01-22. 198: 182: 181: 151: 118: 117: 115: 112: 111: 110: 103: 100: 62: 59: 15: 13: 10: 9: 6: 4: 3: 2: 258: 247: 244: 243: 241: 230: 224: 220: 216: 215: 209: 199: 190: 186: 185: 169: 165: 161: 155: 152: 136: 129: 123: 120: 113: 109: 106: 105: 101: 99: 96: 90: 88: 84: 80: 79:voice channel 75: 73: 69: 60: 58: 56: 51: 49: 45: 41: 36: 34: 30: 26: 22: 246:Multiplexing 223:the original 213: 172:. Retrieved 168:the original 163: 154: 142:. Retrieved 135:the original 122: 91: 76: 64: 52: 37: 33:transmission 28: 24: 18: 229:MIL-STD-188 189:US 5016247 114:References 174:8 October 144:8 October 108:Talkspurt 95:crosstalk 61:Operation 40:Bell Labs 240:Category 102:See also 160:"TAT-1" 194:  68:Duplex 53:Later 210:from 138:(PDF) 131:(PDF) 72:TAT-1 176:2014 146:2014 83:user 29:TASI 23:, a 19:In 242:: 231:). 217:. 162:. 178:. 148:. 27:(

Index

telecommunications
transmission
Bell Labs
transatlantic telephone cables
electronic switching
digital circuit multiplication equipment
Duplex
TAT-1
voice channel
user
voice activity detection
crosstalk
Talkspurt
"Overall Characteristics of a TASI system"
the original
"TAT-1"
the original
US 5016247
public domain material
Federal Standard 1037C
General Services Administration
the original
MIL-STD-188
Category
Multiplexing

Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.