IP-CPRI Altera, IP-CPRI Datasheet - Page 49

• Manufacturer Part Number: IP-CPRI
• Description: IP CORE - Common Public Radio Interface (CPRI)
• Manufacturer: Altera

Specifications of IP-CPRI

• Software Application: IP CORE, Interface And Protocols, HIGH SPEED
• Supported Families: Arria II GX, Cyclone IV GX, HardCopy IV, Stratix IV
• Core Architecture: FPGA
• Core Sub-architecture: Arria, Cyclone, Stratix
• Rohs Compliant: NA
• Lead Free Status / RoHS Status: na
• Lead Free Status / RoHS Status: na

Chapter 4: Functional Description
CPRI MAP Interface Module
December 2010 Altera Corporation
Figure 4–12. Bit Correspondence Between IQ Sample and 32-Bit Avalon-ST Data
You set the oversampling factor to match the frequency of your active data channels.
The CPRI line rate determines the number of bits in the IQ data block of each basic
frame. If your CPRI MegaCore function has a high line rate and a low oversampling
factor, it can accommodate a larger number of active data channels than if the line rate
were lower or the oversampling factor higher.
In 15-bit mode, inside the CPRI MegaCore function, bits 0 and 16 of the Avalon-ST
data are absent from the compact IQ data word representation. Therefore, despite the
fact that in 15-bit mode the IQ data goes out on the data channel in 32-bit words,
formatted as shown in
higher in 15-bit mode.
factors in 16-bit mode, and
in 15-bit mode.
Table 4–4. Maximum Number of Active Data Channels in 16-Bit Mode
Data Channel Bandwidth
LTE (MHz)
Sample Rate
(10
Note to
(1) The maximum number of data channels supported by the CPRI MegaCore function is 24. The numbers in the table
16-Bit Width IQ Sample:
Q:
15
Avalon-ST Data Word in AxC Container:
15-Bit Width IQ Sample:
Q:
14
31
6
that are larger than 24 are hypothetical; the CPRI MegaCore function cannot implement them.
Sample/Sec)
Table
614.4 [120]
1228.8 [240]
2456.7 [480]
3072 [600]
4915.2 [960]
6144 [1200]
4–4:
Table 4–4
Figure
Table 4–5
30
37
3.84
2.5
15
18
3
7
4–12, the maximum number of active data channels is
(1)
(1)
shows the correspondence between these frequency
shows the correspondence between these factors
17 16 15
1 0 15
0
7.68
15
18
5
1
3
7
9
I:
I:
14
15.36
10
—
2
3
4
7
9
CPRI MegaCore Function User Guide
23.04
15
—
1
2
3
5
6
2 1 0
2 1 0
2 1 0
30.72
20
—
—
1
2
3
4
4–25