36:
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115:; the parties at both ends of a call can speak and be heard by the other party simultaneously. The earphone reproduces the speech of the remote party as the microphone transmits the speech of the local party. There is a two-way communication channel between them, or more strictly speaking, there are two communication channels between them.
285:, wherein one must say "over" or another previously designated keyword to indicate the end of transmission, to ensure that only one party transmits at a time. A good analogy for a half-duplex system would be a one-lane road that allows two-way traffic, traffic can only flow in one direction at a time.
415:
Full-duplex audio systems like telephones can create echo, which is distracting to users and impedes the performance of modems. Echo occurs when the sound originating from the far end comes out of the speaker at the near end and re-enters the microphone there and is then sent back to the far end. The
311:
can be used for time allocations for communications in a half-duplex system. For example, station A on one end of the data link could be allowed to transmit for exactly one second, then station B on the other end could be allowed to transmit for exactly one second, and then the cycle repeats. In this
103:
system composed of two or more connected parties or devices that can communicate with one another in both directions. Duplex systems are employed in many communications networks, either to allow for simultaneous communication in both directions between two connected parties or to provide a reverse
402:
Full-duplex has also several benefits over the use of half-duplex. Since there is only one transmitter on each twisted pair there is no contention and no collisions so time is not wasted by having to wait or retransmit frames. Full transmission capacity is available in both directions because the
138:
button. When the local user wants to speak to the remote person, they push this button, which turns on the transmitter and turns off the receiver, preventing them from hearing the remote person while talking. To listen to the remote person, they release the button, which turns on the receiver and
682:) or to synchronize base stations, so that they will transmit and receive at the same time (which increases network complexity and therefore cost, and reduces bandwidth allocation flexibility as all base stations and sectors will be forced to use the same uplink/downlink ratio).
272:) system provides communication in both directions, but only one direction at a time, not simultaneously in both directions. This terminology is not completely standardized between defining organizations, and in radio communication some sources classify this mode as
677:
each other (as they transmit and receive in different sub-bands) and therefore will normally not interfere with each other. Conversely, with time-division duplexing systems, care must be taken to keep guard times between neighboring base stations (which decreases
406:
Some computer-based systems of the 1960s and 1970s required full-duplex facilities, even for half-duplex operation, since their poll-and-response schemes could not tolerate the slight delays in reversing the direction of transmission in a half-duplex line.
220:
provide a simplex circuit in the ITU sense; only one party at a time can talk, while the other listens until it can hear an opportunity to transmit. The transmission medium (the radio signal over the air) can carry information in only one direction.
398:
use the same channels in each direction simultaneously. In any case, with full-duplex operation, the cable itself becomes a collision-free environment and doubles the maximum total transmission capacity supported by each
Ethernet connection.
501:
data rates or utilization. As the amount of uplink data increases, more communication capacity can be dynamically allocated, and as the traffic load becomes lighter, capacity can be taken away. The same applies in the downlink direction.
442:
modem standards require echo cancellation. Echo cancelers are available as both software and hardware implementations. They can be independent components in a communications system or integrated into the communication system's
661:
Frequency-division duplexing can be efficient in the case of symmetric traffic. In this case, time-division duplexing tends to waste bandwidth during the switch-over from transmitting to receiving, has greater inherent
393:
inside the same jacket, or two optical fibers which are directly connected to each networked device: one pair or fiber is for receiving packets, while the other is for sending packets. Other
Ethernet variants, such as
642:
station. The repeater station must be able to send and receive a transmission at the same time and does so by slightly altering the frequency at which it sends and receives. This mode of operation is referred to as
658:
Frequency-division duplex systems can extend their range by using sets of simple repeater stations because the communications transmitted on any single frequency always travel in the same direction.
331:
A simple illustration of a full-duplex communication system. Full-duplex is not common in handheld radios as shown here due to the cost and complexity of common duplexing methods, but is used in
422:
is a signal-processing operation that subtracts the far-end signal from the microphone signal before it is sent back over the network. Echo cancellation is important technology allowing
378:
communication which uses two distinct channels, one for each direction. From the user perspective, the technical difference does not matter and both variants are commonly referred to as
978:
104:
path for the monitoring and remote adjustment of equipment in the field. There are two types of duplex communication systems: full-duplex (FDX) and half-duplex (HDX).
296:
is needed and is shared alternately between the two directions. For example, a walkie-talkie or a DECT phone or so-called TDD 4G or 5G phones requires only a single
126:
system, both parties can communicate with each other, but not simultaneously; the communication is one direction at a time. An example of a half-duplex device is a
1488:
1455:
374:
There is a technical distinction between full-duplex communication, which uses a single physical communication channel for both directions simultaneously, and
304:
in the so-called FDD mode is a full-duplex device, and generally requires two frequencies to carry the two simultaneous voice channels, one in each direction.
1478:
1927:
1228:
278:. Typically, once one party begins a transmission, the other party on the channel must wait for the transmission to complete, before replying.
1108:
1308:
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467:) for dividing forward and reverse communication channels on the same physical communications medium, they are known as duplexing methods.
435:
1356:
673:
Another advantage of frequency-division duplexing is that it makes radio planning easier and more efficient since base stations do not
359:
networks are full-duplex since they allow both callers to speak and be heard at the same time. Full-duplex operation is achieved on a
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definition is a communications channel that operates in one direction at a time, but that may be reversible; this is termed
1221:
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This feedback path may be acoustic, through the air, or it may be mechanically coupled, for example in a telephone handset.
355:) system allows communication in both directions, and, unlike half-duplex, allows this to happen simultaneously. Land-line
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to separate outward and return signals. It emulates full-duplex communication over a half-duplex communication link.
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turns off the transmitter. This terminology is not completely standardized, and some sources define this mode as
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system, both parties can communicate with each other simultaneously. An example of a full-duplex device is
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566:, can be considered as time-division duplexing systems, albeit not TDMA with fixed frame-lengths.
509:(TTG) is the gap (time) between a downlink burst and the subsequent uplink burst. Similarly, the
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Design and
Analysis of Duplexing Modes and Forwarding Protocols for OFDM(A) Relay Links
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connections achieve full-duplex operation by making simultaneous use of two physical
2178:
292:, at the cost of reducing the overall bidirectional throughput, since only a single
213:, information flows only from the transmitter site to multiple receivers. A pair of
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2013:
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951:
Electronics
Explained: Fundamentals for Engineers, Technicians, and Makers, 2nd Ed
889:
Milnor, J.W. and G.A. Randall. "The
Newfoundland-Azores High-Speed Duplex Cable".
2143:
1998:
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1021:
This definition is accredited by the
American National Standards Institute (ANSI)
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In half-duplex systems, if more than one party transmits at the same time, a
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225:
217:
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150:, in which one device transmits and the others can only listen. Examples are
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513:(RTG) is the gap between an uplink burst and the subsequent downlink burst.
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in 1928. The same definition for a simplex radio channel was used by the
202:
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1978:
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1192:. Aalto University publication series DOCTORAL DISSERTATIONS, 81/2014.
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An example of a half-duplex system is a two-party system such as a
232:
when describing the half-duplex and simplex capacity of their new
2548:
2533:
1751:
1336:
903:
Report of the
Committee on Public Emergency Service Communication
583:, variants using the time-compression multiplex (TCM) line system
530:
651:. Uplink and downlink sub-bands are said to be separated by the
307:
In automatic communications systems such as two-way data-links,
170:. In these devices, the communication is only in one direction.
2578:
2538:
1860:
1374:
1331:
586:
574:
489:
Time-division duplexing is flexible in the case where there is
241:
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sound then reappears at the original source end but delayed.
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2500:
1808:
1450:
718:
594:
569:
423:
327:
256:
880:, 2000, Inst. of Electrical and Electronic Engineers, p.1053
878:
The IEEE Authoritative
Dictionary of Standard Terms, 7th Ed.
2505:
706:
693:
689:
540:
260:
A simple illustration of a half-duplex communication system
146:
Systems that do not need duplex capability may instead use
685:
Examples of frequency-division duplexing systems include:
178:
1113:. World Scientific Publishing Company. pp. 519–520.
1110:
Telecommunications
Engineering: Principles And Practice
534:
524:
27:
Communication flowing simultaneously in both directions
985:. International Telecommunications Union (ITU) website
516:
Examples of time-division duplexing systems include:
1011:. Alliance for Telecommunications Industry Solutions
638:
operation, where an operator is attempting to use a
1135:"TTG vs RTG-What is TTG and RTG Gaps in WIMAX, LTE"
1162:
1594:
319:occurs, resulting in lost or distorted messages.
288:Half-duplex systems are usually used to conserve
2699:
1086:. Cambridge University Press. pp. 129–132.
1079:
924:. New Delhi: Dorling Kindersley. pp. 6–7.
600:
193:that sends information in one direction only.
1621:
1222:
426:to achieve good full-duplex performance. The
1589:
913:
911:
2636:Global telecommunications regulation bodies
1106:
1100:
371:. Modern cell phones are also full-duplex.
2672:
1628:
1614:
1229:
1215:
1080:Greenstein, Shane; Stango, Victor (2006).
917:
470:
1157:
943:
941:
908:
845:
843:
815:
813:
403:send and receive functions are separate.
312:scheme, the channel is never left idle.
300:for bidirectional communication, while a
80:Learn how and when to remove this message
1185:
450:
326:
255:
177:
43:This article includes a list of general
947:
849:
819:
14:
2700:
1635:
938:
856:. Elsevier Science. pp. 170–171.
840:
810:
1609:
1210:
973:
971:
820:Lindley, Matthew (12 February 2023).
198:International Telecommunication Union
2682:
410:
246:National Fire Protection Association
29:
997:
870:
24:
1151:
968:
49:it lacks sufficient corresponding
25:
2719:
954:. Elsevier Science. p. 161.
921:Analog and Digital Communications
634:The method is frequently used in
2681:
2671:
2662:
2661:
2650:
2271:Free-space optical communication
593:(DSL) standard developed by the
34:
1127:
1073:
1049:
1024:
891:A.I.E.E. Electrical Engineering
790:
666:, and may require more complex
607:Frequency-division multiplexing
511:receive/transmit transition gap
507:transmit/receive transition gap
983:Terms and Definitions Database
896:
883:
322:
251:
182:Simplex wireless communication
13:
1:
1546:Delay and disruption tolerant
1107:Gyasi-Agyei, Amoakoh (2019).
803:
552:carrier-sense multiple access
234:transatlantic telegraph cable
209:For example, in TV and radio
2657:Telecommunication portal
2438:Telecommunications equipment
613:Frequency-division duplexing
601:Frequency-division duplexing
560:Wireless local area networks
7:
2174:Alexander Stepanovich Popov
1083:Standards and Public Policy
853:Radio Spectrum Conservation
724:
533:for data communications on
523:for data communications on
113:plain old telephone service
10:
2724:
1878:Telecommunications history
918:Sudakshina, Kundu (2010).
822:"What is a Two-Way Radio?"
604:
484:time-division multiplexing
309:time-division multiplexing
173:
2645:
2587:
2524:
2486:Public Switched Telephone
2446:
2410:
2367:
2308:
2298:telecommunication circuit
2259:Fiber-optic communication
2242:
2004:Francis Blake (telephone)
1951:
1799:Optical telecommunication
1643:
1580:
1545:
1517:
1464:
1426:
1417:
1398:
1383:
1365:
1322:
1299:
1257:
1248:
1186:Riihonen, Taneli (2014).
850:Gosling, William (2000).
772:Radio resource management
2397:Orbital angular-momentum
1834:Satellite communications
1673:Communications satellite
1057:"Cell phone Frequencies"
783:
627:operate using different
605:Not to be confused with
554:, for example 2-wire or
482:) is the application of
2276:Molecular communication
2099:Gardiner Greene Hubbard
1928:Undersea telegraph line
1663:Cable protection system
948:Frenzel, Louis (2017).
905:. NFPA 1221, May, 2002.
591:digital subscriber line
476:Time-division duplexing
471:Time-division duplexing
445:central processing unit
64:more precise citations.
2708:Communication circuits
2418:Communication protocol
2204:Charles Sumner Tainter
2019:Walter Houser Brattain
1964:Edwin Howard Armstrong
1772:Information revolution
1568:Dynamic Source Routing
1238:Channel access methods
457:channel access methods
344:
261:
228:company used the term
183:
154:radio and television,
2392:Polarization-division
2124:Narinder Singh Kapany
2089:Erna Schneider Hoover
2009:Jagadish Chandra Bose
1989:Alexander Graham Bell
1720:online video platform
1009:ATIS Telecom Glossary
777:Simplex communication
732:Communication channel
451:Full-duplex emulation
363:through the use of a
330:
294:communication channel
259:
191:communication channel
187:Simplex communication
181:
148:simplex communication
2234:Vladimir K. Zworykin
2194:Almon Brown Strowger
2164:Charles Grafton Page
1819:Prepaid mobile phone
1747:Electrical telegraph
1242:media access control
1159:Tanenbaum, Andrew S.
742:Double-track railway
206:in other contexts.
168:surveillance cameras
164:wireless microphones
97:communication system
2184:Johann Philipp Reis
1943:Wireless revolution
1905:The Telephone Cases
1762:Hydraulic telegraph
1466:Collision avoidance
737:Crossband operation
680:spectral efficiency
629:carrier frequencies
461:point-to-multipoint
156:garage door openers
2382:Frequency-division
2359:Telephone exchange
2229:Charles Wheatstone
2159:Jun-ichi Nishizawa
2134:Innocenzo Manzetti
2069:Reginald Fessenden
1804:Optical telegraphy
1637:Telecommunications
1428:Collision recovery
828:. WiseGeek website
550:networks based on
543:wireless telephony
463:networks (such as
345:
262:
236:completed between
184:
2695:
2694:
2433:Store and forward
2428:Data transmission
2342:Network switching
2293:Transmission line
2139:Guglielmo Marconi
2104:Internet pioneers
1969:Mohamed M. Atalla
1938:Whistled language
1603:
1602:
1582:Duplexing methods
1576:
1575:
1413:
1412:
1199:978-952-60-5715-6
1169:. Prentice Hall.
1165:Computer Networks
1093:978-1-139-46075-0
757:Four-wire circuit
699:Mobile technology
619:) means that the
465:cellular networks
420:Echo cancellation
411:Echo cancellation
90:
89:
82:
16:(Redirected from
2715:
2685:
2684:
2675:
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2655:
2654:
2653:
2526:Notable networks
2516:Wireless network
2456:Cellular network
2448:Types of network
2423:Computer network
2310:Network topology
2224:Thomas A. Watson
2079:Oliver Heaviside
2064:Philo Farnsworth
2039:Daniel Davis Jr.
2014:Charles Bourseul
1974:John Logie Baird
1683:Data compression
1678:Computer network
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653:frequency offset
369:telephone hybrid
361:two-wire circuit
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60:this article by
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1999:Tim Berners-Lee
1947:
1767:Information Age
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556:hubbed Ethernet
548:packet switched
537:mobile networks
527:mobile networks
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341:cordless phones
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2214:Camille Tissot
2211:
2206:
2201:
2196:
2191:
2189:Claude Shannon
2186:
2181:
2179:Tivadar Puskás
2176:
2171:
2166:
2161:
2156:
2151:
2149:Antonio Meucci
2146:
2141:
2136:
2131:
2126:
2121:
2119:Charles K. Kao
2116:
2111:
2106:
2101:
2096:
2094:Harold Hopkins
2091:
2086:
2081:
2076:
2071:
2066:
2061:
2056:
2051:
2046:
2041:
2036:
2031:
2026:
2021:
2016:
2011:
2006:
2001:
1996:
1994:Emile Berliner
1991:
1986:
1981:
1976:
1971:
1966:
1961:
1955:
1953:
1949:
1948:
1946:
1945:
1940:
1935:
1933:Videotelephony
1930:
1925:
1924:
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1918:
1908:
1901:
1896:
1890:
1885:
1880:
1875:
1870:
1869:
1868:
1863:
1858:
1848:
1847:
1846:
1836:
1831:
1829:Radiotelephone
1826:
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1806:
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1796:
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1784:
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1717:
1715:Internet video
1707:
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1555:
1549:
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1529:
1523:
1521:
1519:Collision-free
1515:
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1496:
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839:
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567:
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538:
528:
472:
469:
452:
449:
412:
409:
324:
321:
253:
250:
218:two-way radios
175:
172:
101:point-to-point
88:
87:
70:September 2015
42:
40:
33:
26:
9:
6:
4:
3:
2:
2720:
2709:
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2426:
2424:
2421:
2419:
2416:
2415:
2413:
2409:
2403:
2402:Code-division
2400:
2398:
2395:
2393:
2390:
2388:
2387:Time-division
2385:
2383:
2380:
2378:
2375:
2374:
2372:
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2333:
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2328:
2326:
2323:
2321:
2318:
2317:
2315:
2313:and switching
2311:
2307:
2299:
2296:
2295:
2294:
2291:
2287:
2284:
2283:
2282:
2279:
2277:
2274:
2272:
2269:
2265:
2264:optical fiber
2262:
2261:
2260:
2257:
2255:
2254:Coaxial cable
2252:
2251:
2249:
2247:
2241:
2235:
2232:
2230:
2227:
2225:
2222:
2220:
2217:
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2207:
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2202:
2200:
2197:
2195:
2192:
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2182:
2180:
2177:
2175:
2172:
2170:
2169:Radia Perlman
2167:
2165:
2162:
2160:
2157:
2155:
2152:
2150:
2147:
2145:
2142:
2140:
2137:
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2127:
2125:
2122:
2120:
2117:
2115:
2112:
2110:
2107:
2105:
2102:
2100:
2097:
2095:
2092:
2090:
2087:
2085:
2082:
2080:
2077:
2075:
2072:
2070:
2067:
2065:
2062:
2060:
2059:Lee de Forest
2057:
2055:
2054:Thomas Edison
2052:
2050:
2047:
2045:
2044:Donald Davies
2042:
2040:
2037:
2035:
2032:
2030:
2029:Claude Chappe
2027:
2025:
2022:
2020:
2017:
2015:
2012:
2010:
2007:
2005:
2002:
2000:
1997:
1995:
1992:
1990:
1987:
1985:
1982:
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1977:
1975:
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1967:
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1962:
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1900:
1897:
1894:
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1879:
1876:
1874:
1873:Smoke signals
1871:
1867:
1864:
1862:
1859:
1857:
1854:
1853:
1852:
1851:Semiconductor
1849:
1845:
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1711:
1710:Digital media
1708:
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1471:
1469:
1467:
1463:
1457:
1454:
1452:
1449:
1447:
1444:
1442:
1441:Slotted ALOHA
1439:
1437:
1434:
1433:
1431:
1429:
1425:
1422:
1420:
1416:
1406:
1405:
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1275:
1273:
1270:
1269:
1268:
1265:
1264:
1262:
1260:
1256:
1253:
1251:
1250:Channel-based
1247:
1243:
1239:
1232:
1227:
1225:
1220:
1218:
1213:
1212:
1209:
1201:
1195:
1191:
1190:
1184:
1183:
1178:
1176:0-13-038488-7
1172:
1167:
1166:
1160:
1156:
1155:
1136:
1130:
1122:
1120:9789811200274
1116:
1112:
1111:
1103:
1095:
1089:
1085:
1084:
1076:
1062:
1061:HowStuffWorks
1058:
1052:
1037:
1036:www.pcmag.com
1033:
1032:"half-duplex"
1027:
1010:
1006:
1005:"Half-duplex"
1000:
984:
980:
974:
972:
963:
961:9780128118795
957:
953:
952:
944:
942:
933:
931:9788131731871
927:
923:
922:
914:
912:
904:
899:
892:
886:
879:
873:
865:
863:9780750637404
859:
855:
854:
846:
844:
827:
823:
816:
814:
809:
793:
789:
778:
775:
773:
770:
768:
765:
763:
760:
758:
755:
753:
750:
748:
745:
743:
740:
738:
735:
733:
730:
729:
720:
717:
714:
712:
708:
704:
700:
697:
695:
691:
688:
687:
686:
683:
681:
676:
671:
669:
665:
659:
656:
654:
650:
646:
641:
637:
632:
630:
626:
622:
618:
614:
608:
596:
592:
588:
585:
582:
578:
576:
573:
571:
568:
565:
561:
557:
553:
549:
545:
542:
539:
536:
532:
529:
526:
522:
519:
518:
517:
514:
512:
508:
503:
500:
496:
492:
487:
485:
481:
477:
468:
466:
462:
458:
448:
446:
441:
437:
433:
429:
425:
421:
417:
408:
404:
400:
397:
392:
391:twisted pairs
388:
383:
381:
377:
372:
370:
366:
362:
358:
354:
350:
342:
338:
334:
329:
320:
318:
313:
310:
305:
303:
299:
295:
291:
286:
284:
283:walkie-talkie
279:
277:
276:
271:
267:
258:
249:
247:
243:
239:
235:
231:
227:
226:Western Union
222:
219:
216:
215:walkie-talkie
212:
207:
205:
204:
199:
194:
192:
188:
180:
171:
169:
165:
161:
160:baby monitors
157:
153:
149:
144:
142:
137:
133:
132:two-way radio
129:
128:walkie-talkie
125:
121:
116:
114:
110:
105:
102:
98:
95:
84:
81:
73:
63:
59:
53:
52:
46:
41:
32:
31:
19:
2369:Multiplexing
2244:Transmission
2209:Nikola Tesla
2199:Henry Sutton
2154:Samuel Morse
2084:Robert Hooke
2049:Amos Dolbear
1984:John Bardeen
1903:
1883:Telautograph
1787:Mobile phone
1742:Edholm's law
1725:social media
1658:Broadcasting
1581:
1419:Packet-based
1188:
1164:
1138:. Retrieved
1129:
1109:
1102:
1082:
1075:
1064:. Retrieved
1060:
1051:
1039:. Retrieved
1035:
1026:
1013:. Retrieved
1008:
999:
987:. Retrieved
982:
950:
920:
902:
898:
890:
885:
877:
872:
852:
830:. Retrieved
825:
792:
767:Push-to-talk
762:Multiplexing
701:, including
684:
674:
672:
660:
657:
652:
648:
644:
633:
616:
612:
611:
546:Half-duplex
515:
510:
506:
504:
488:
479:
475:
474:
459:are used in
454:
418:
414:
405:
401:
384:
379:
376:dual-simplex
375:
373:
352:
348:
346:
314:
306:
287:
280:
273:
269:
265:
263:
238:Newfoundland
229:
223:
211:broadcasting
208:
201:
195:
186:
185:
145:
136:push-to-talk
123:
119:
117:
108:
106:
93:
91:
76:
67:
48:
18:Dual simplex
2569:NPL network
2281:Radio waves
2219:Alfred Vail
2129:Hedy Lamarr
2114:Dawon Kahng
2074:Elisha Gray
2034:Yogen Dalal
1959:Nasir Ahmed
1893:Teleprinter
1757:Heliographs
1015:27 February
989:27 February
832:27 February
716:IEEE 802.16
649:offset mode
645:duplex mode
621:transmitter
581:U interface
380:full duplex
365:hybrid coil
349:full-duplex
323:Full duplex
266:half-duplex
252:Half duplex
203:half duplex
134:that has a
120:half-duplex
109:full-duplex
62:introducing
2615:Antarctica
2574:Toasternet
2496:Television
1979:Paul Baran
1911:Television
1895:(teletype)
1888:Telegraphy
1866:transistor
1844:Phryctoria
1814:Photophone
1792:Smartphone
1782:Mass media
1527:Token Ring
1140:2021-06-05
1066:2019-02-14
893:. May 1931
876:"Simplex"
826:Technology
804:References
396:1000BASE-T
337:cellphones
333:telephones
302:cell phone
124:semiduplex
45:references
2599:Americas
2588:Locations
2559:Internet2
2320:Bandwidth
2024:Vint Cerf
1921:streaming
1899:Telephone
1839:Semaphore
1730:streaming
1532:Token bus
1509:CSMA/CARP
668:circuitry
636:ham radio
579:ISDN BRI
564:Bluetooth
491:asymmetry
357:telephone
317:collision
298:frequency
290:bandwidth
248:in 2002.
152:broadcast
2702:Category
2667:Category
2554:Internet
2544:CYCLADES
2461:Ethernet
2411:Concepts
2335:terminal
2286:wireless
2109:Bob Kahn
1952:Pioneers
1777:Internet
1668:Cable TV
1537:MS-ALOHA
1342:TD-SCDMA
1161:(2003).
979:"Duplex"
752:Duplexer
725:See also
711:CDMA2000
640:repeater
625:receiver
521:UMTS-TDD
499:downlink
387:Ethernet
240:and the
2687:Commons
2677:Outline
2630:Oceania
2549:FidoNet
2534:ARPANET
2347:circuit
1916:digital
1645:History
1489:CSMA/CA
1456:CSMA/CD
1446:R-ALOHA
1375:HC-SDMA
1357:MC-CDMA
1352:FH-CDMA
1347:DS-CDMA
1337:TD-CDMA
1309:MF-TDMA
1277:SC-FDMA
1041:20 June
664:latency
531:LTE-TDD
493:of the
275:simplex
230:simplex
174:Simplex
141:simplex
58:improve
2625:Europe
2595:Africa
2579:Usenet
2539:BITNET
2476:Mobile
2352:packet
1861:MOSFET
1856:device
1653:Beacon
1332:W-CDMA
1196:
1173:
1117:
1090:
958:
928:
860:
587:G.fast
575:PACTOR
495:uplink
455:Where
438:, and
424:modems
242:Azores
166:, and
94:duplex
47:, but
2608:South
2603:North
2564:JANET
2501:Telex
2491:Radio
2330:Nodes
2325:Links
2246:media
1824:Radio
1809:Pager
1737:Drums
1703:video
1698:image
1688:audio
1558:VANET
1553:MANET
1479:MACAW
1451:AX.25
1436:ALOHA
1314:STDMA
1272:OFDMA
784:Notes
719:WiMax
595:ITU-T
570:WiMAX
385:Many
367:in a
189:is a
118:In a
107:In a
99:is a
2620:Asia
2506:UUCP
2466:ISDN
1484:CSMA
1474:MACA
1400:PAMA
1385:PDMA
1367:SDMA
1324:CDMA
1301:TDMA
1289:WDMA
1259:FDMA
1240:and
1194:ISBN
1171:ISBN
1115:ISBN
1088:ISBN
1043:2023
1017:2023
991:2023
956:ISBN
926:ISBN
858:ISBN
834:2023
709:and
707:UMTS
694:VDSL
692:and
690:ADSL
675:hear
623:and
589:, a
562:and
541:DECT
505:The
497:and
440:V.90
436:V.56
432:V.34
428:V.32
339:and
224:The
196:The
130:, a
2511:WAN
2481:NGN
2471:LAN
1752:Fax
1693:DCT
1595:FDD
1590:TDD
1563:DTN
1504:HCF
1499:PCF
1494:DCF
1284:WDM
1267:FDM
703:LTE
655:.
647:or
631:.
617:FDD
480:TDD
353:FDX
270:HDX
122:or
2704::
1059:.
1034:.
1007:.
981:.
970:^
940:^
910:^
842:^
824:.
812:^
705:,
670:.
558:,
535:4G
525:3G
447:.
434:,
430:,
382:.
347:A
335:,
264:A
162:,
158:,
143:.
92:A
2638:)
2634:(
1629:e
1622:t
1615:v
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