Digital Signal Processing Reference
In-Depth Information
TDMA
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1
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TDMA: 8 user communicate in time multiplex on one frequency
or onto two frequencies (uplink und downlink)
f
(MHz)
FDMA / TDMA in the E-Band
1762 ,6
1762 ,4
1762 ,2
1762 ,0
1
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1761 ,8
1761 ,6
1761 ,4
1761 ,2
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1760 ,8
1760 ,6
1760 ,4
1760 ,2
70
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t
Time slots for different conversations in different channels (B = 200 kHz)
Illustration 278:
Frequency- and time-multiplexing in the GSM-procedure
Modern ADSL-systems operate above the ISDN frequency band and utilize a frequency
range of approximately up to 1.1 MHz. A total of 256 carrier frequencies with a distance
of 4 kHz (for downstream) are used. Each carrier can as a rule take on up to 32 states in
the signal space.
