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* Non-continuous transmission makes handoff simpler
* Slots can be assigned on demand in dynamic TDMA
* Less stringent power control than [[
* Higher synchronization overhead than CDMA
* Advanced [[Equalization (communications)|equalization]] may be necessary for high data rates if the channel is "frequency selective" and creates [[Intersymbol interference]]
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* Pulsating power envelope: [[Electromagnetic interference|interference]] with other devices
== In mobile phone systems ==
=== 2G systems ===
Most 2G cellular systems, with the notable exception of [[IS-95]], are based on TDMA. [[GSM]], [[D-AMPS]], [[Personal Digital Cellular|PDC]], [[iDEN]], and [[Personal Handy-phone System|PHS]] are examples of TDMA cellular systems.
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Initial synchronization of a phone requires even more care. Before a mobile transmits there is no way to actually know the offset required. For this reason, an entire time slot has to be dedicated to mobiles attempting to contact the network; this is known as the [[random-access channel]] (RACH) in GSM. The mobile attempts to broadcast at the beginning of the time slot, as received from the network. If the mobile is located next to the base station, there will be no time delay and this will succeed. If, however, the mobile phone is at just less than 35 km from the base station, the time delay will mean the mobile's broadcast arrives at the very end of the time slot. In that case, the mobile will be instructed to broadcast its messages starting nearly a whole time slot earlier than would be expected otherwise. Finally, if the mobile is beyond the 35 km cell range in GSM, then the RACH will arrive in a neighbouring time slot and be ignored. It is this feature, rather than limitations of power, that limits the range of a GSM cell to 35 km when no special extension techniques are used. By changing the synchronization between the uplink and downlink at the base station, however, this limitation can be overcome. {{citation needed|date=November 2014}}
=== 3G systems ===
{{Expand section|date=November 2014}}
Although most major 3G systems are primarily based upon [[CDMA]],<ref>{{Cite book|url=https://books.google.com/books?id=zLz-CwAAQBAJ&q=3G+systems+are+primarily+based+upon+CDMA&pg=PT24|title=Principles of Modern Wireless Communication Systems|last=K. Jagannatham|first=Aditya|publisher=McGraw-Hill Education|year=2016|isbn=9789339220037}}</ref> time-division duplexing (TDD), packet scheduling (dynamic TDMA) and packet oriented multiple access schemes are available in 3G form, combined with CDMA to take advantage of the benefits of both technologies.
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