154:(OTDR; for optical cables) can be used to locate the damaged part of a cable. These instruments work by sending a short pulsed signal into the cable and measuring how long the reflection takes to return. If only reflection magnitudes are desired, however, and exact fault locations are not required, VSWR bridges perform a similar but lesser function for
81:
Because the principles are the same, this concept is perhaps easiest to understand when considering an optical fiber. Imperfections in the glass create mirrors that reflect the light back along the fiber.
58:. Some of the signal power may be reflected back to its origin rather than being carried all the way along the cable to the far end. This happens because imperfections in the cable cause
113:. This effect is compounded if multiple discontinuities cause additional portions of the remaining signal to be reflected back to the transmitter. This is a fundamental problem with the
124:
strike the receiver at different intervals making it difficult for the receiver to accurately detect data values on the signal. The effects can resemble those of
62:
mismatches and non-linear changes in the cable characteristics. These abrupt changes in characteristics cause some of the transmitted signal to be reflected. In
120:
When a returning reflection strikes another discontinuity, some of the signal rebounds in the original signal direction, creating multiple echo effects. These
132:
236:
51:
261:
114:
151:
385:
173:
in all cables and connectors, with no impedance discontinuities in the entire cable system. When a sufficient degree of
375:
67:
380:
365:
147:
135:
390:
221:
170:
192:
method, valid for both linear and non-linear models, evaluates the reflection's effects in an electric line.
241:
206:
201:
131:
90:
75:
370:
59:
310:
162:
47:
43:
226:
216:
174:
71:
31:
110:
285:
231:
189:
139:
106:
98:
178:
155:
101:
and other effects because a portion of a transmitted signal will be reflected back to the
63:
161:
The combination of the effects of signal attenuation and impedance discontinuities on a
182:
166:
94:
17:
146:
Because damage to the cable can cause reflections, an instrument called an electrical
359:
55:
211:
121:
334:
27:
When a transmitted signal reflects back through the medium it was transmitted over
102:
86:
70:(VSWR) with a VSWR bridge. The ratio of energy bounced back depends on the
66:(RF) practice this is often measured in a dimensionless ratio known as
125:
39:
130:
262:"Physics behind signal reflections and series termination"
169:. Proper network operation depends on constant
336:AN-807 Reflections: Computations and Waveforms
185:, or both, can sometimes reduce the problems.
117:method of connecting electronic components.
8:
286:"What Is Signal Reflection? (with pictures)"
74:. Mathematically, it is defined using the
237:Reflections of signals on conducting lines
253:
266:Electrical Engineering Stack Exchange
105:device rather than continuing to the
7:
150:(ETDR; for electrical cables) or an
25:
152:optical time-domain reflectometer
85:Impedance discontinuities cause
1:
68:voltage standing wave ratio
407:
148:time-domain reflectometer
136:Time-domain reflectometer
311:"Why Reflections Happen"
222:Ground-penetrating radar
171:characteristic impedance
315:www.signalintegrity.com
242:Reflection phase change
207:Digital subscriber line
202:Crosstalk (electronics)
18:Reflection (electrical)
386:Electrical engineering
143:
91:attenuation distortion
76:reflection coefficient
134:
163:communications link
48:transmission medium
376:Geometrical optics
227:Impedance matching
217:Fresnel reflection
177:is not practical,
175:impedance matching
144:
72:impedance mismatch
32:telecommunications
381:Electronic design
366:Radio electronics
36:signal reflection
16:(Redirected from
398:
350:
349:
347:
346:
341:
331:
325:
324:
322:
321:
307:
301:
300:
298:
297:
282:
276:
275:
273:
272:
258:
232:Signal integrity
190:Bergeron diagram
179:echo suppressors
140:electrical cable
21:
406:
405:
401:
400:
399:
397:
396:
395:
391:Physical optics
356:
355:
354:
353:
344:
342:
339:
333:
332:
328:
319:
317:
309:
308:
304:
295:
293:
290:All the Science
284:
283:
279:
270:
268:
260:
259:
255:
250:
198:
183:echo cancellers
142:fault detection
109:, much like an
64:radio frequency
28:
23:
22:
15:
12:
11:
5:
404:
402:
394:
393:
388:
383:
378:
373:
368:
358:
357:
352:
351:
326:
302:
277:
252:
251:
249:
246:
245:
244:
239:
234:
229:
224:
219:
214:
209:
204:
197:
194:
167:insertion loss
122:forward echoes
95:standing waves
38:occurs when a
26:
24:
14:
13:
10:
9:
6:
4:
3:
2:
403:
392:
389:
387:
384:
382:
379:
377:
374:
372:
369:
367:
364:
363:
361:
338:
337:
330:
327:
316:
312:
306:
303:
291:
287:
281:
278:
267:
263:
257:
254:
247:
243:
240:
238:
235:
233:
230:
228:
225:
223:
220:
218:
215:
213:
210:
208:
205:
203:
200:
199:
195:
193:
191:
186:
184:
180:
176:
172:
168:
164:
159:
157:
153:
149:
141:
137:
133:
129:
127:
123:
118:
116:
112:
108:
104:
100:
96:
92:
88:
83:
79:
77:
73:
69:
65:
61:
57:
56:optical fiber
53:
49:
45:
41:
37:
33:
19:
343:. Retrieved
335:
329:
318:. Retrieved
314:
305:
294:. Retrieved
292:. 2023-04-22
289:
280:
269:. Retrieved
265:
256:
212:Project Echo
187:
160:
145:
119:
103:transmitting
84:
80:
52:copper cable
50:, such as a
35:
29:
371:Electricity
115:daisy chain
87:attenuation
44:transmitted
360:Categories
345:2023-06-03
320:2023-06-03
296:2023-06-03
271:2023-06-03
248:References
165:is called
156:RF cables
60:impedance
196:See also
107:receiver
46:along a
99:ringing
126:jitter
54:or an
40:signal
340:(PDF)
188:The
138:for
111:echo
181:or
42:is
30:In
362::
313:.
288:.
264:.
158:.
128:.
97:,
93:,
89:,
78:.
34:,
348:.
323:.
299:.
274:.
20:)
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
