GC5316 Datasheet, PDF (26/75 Pages) Texas Instruments – HIGH-DENSITY DIGITAL DOWNCONVERTER AND UPCONVERTER

GC5316
SLWS154A − JANUARY 2004 − REVISED MARCH 2004
www.ti.com
The outputs of all DUCs drive four independent complex sum chains. Any DUC can contribute (or not) to any or all
of the four sum chains. The output of a DUC block’s sum chain drives the sum chain input of the next block. The first
DUC to output data is DUC0, while the last is DUC11. The four outputs of a DUC are the sum of all the contributing
channels of all the higher numbered DUC blocks and itself. The sum chain inputs of DUC 11 are grounded. Within
the chain, all DUC blocks from 0 up to the highest numbered DUC in use must be turned on otherwise the sum chain
is broken.
The transmit output interface takes the four summed chains of DUC output data from the output of DUC 0 and then
scales and rounds to a user-programmed number of bits. Composite power meters with programmable integration
periods and intervals compute the power in each of the four output streams. The data is then formatted for output
over the four tx_data_out outputs.
3.1 Digital Upconvert Block (DUC)
4 sign on top
16 data
15 zeros on bottom
P ilot
I nsertion
(UMTS only)
16 ¹⁶
34
36
Se ria l
I,Q
S e ria l
Inte rfa c e
G a in
5 guard on top
18 data
13 on bottom
18
Round
R MS
Power Meter
32
F requency
16
P ha se
N CO
18
Programm able
FI R Filter
Interp by 2
18
C ompensating
FI R Filter
I nterp by 2
18
Six Stage
CI C Filter
I nterp 4 − 32
18
Delay Adjust
CDMA A& Bchannels, or1 UMTS channel
Sum 1
Input
FromPrevious TransmitChannel
Sum2
Input
Sum3
Input
Sum4
Input
Sum 1
Output
Sum2
Output
Sum3
Output
Sum4
Output
To Next Transmit Channel
Figure 21. Digital Upconvert Block
This section describes the functions available in each of the 12 DUC blocks. Each DUC block has its own register
set and may be programmed individually. The final output rates must match since they are added together.
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