What is the difference between TDMA and TDD?

What is the difference between TDMA and TDD?

tdd vs tdma

dear pmonon;

TDD stands for time division duplix, which means that the mobile sends it's data in a specific time and recieve the data from the BTS in another time.

TDMA stands for time division multible access, which means that the mobiles share the same resources but in different times.

i wish i was helpfull.

thanks

tdd tdma


TDD- Time Division Duplex & TDMA - Time Division Multiple Access

tdma tdd

Hi

TDD is a duplex method which means that time is divided into time slots and te user sends data in some time slots and receive data in the rest of time slots

TDMA is a multiple access method which means that time is divided into time slots and each user can access the medium -either transmit or receive- in certain time slots and other users use the medium in the rest time slots.

in order to deep understand the differences you should understand he differences between Multiple Access methods -which allow many users o share the medium - and Duplex methods wich identify how Tx and Rx relate to each other in time or frequency or .....

Salam
Hossam Alzomor
www(.)i-g(.)org

difference between tdma and tdd

Hi pmonon,

TDD & TDMA are completely different.

TDD:
to establish a commmunication (a call for example in GSM) you will need from your mobile to send information to the network (Base station in GSM): this is the uplink direction. Conversely you will receive information from the network to the mobile: this is the downlink direction. Then you need two directions (duplex) to make a communication.
The TDD duplex mode tells you that you will use of these directions (downlink or uplink) alternatively to make your communication (i.e;: downlink then uplink then downlink then uplink and so on...). The duration of each direction transmission depends on the technology.

TDMA:
TDMA is multiple access method, meaning that it describe HOW you will share the radio resource (i.e. the frequencies in GSM or the codes in UMTS).
TDMA tells you that you will use the radio resource only during a given time. Usually this is represented by the use of slots that you can use at a certain time. That is way there are called "timeslots".

I hope this will help.

Gh

Re: difference between tdma and tdd

"demonda" your post is really helpful