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
May 2011 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 IP core 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 IP core, 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
15-bit mode.
16-bit mode, and
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 IP core is 24. The numbers in the table that are
16-Bit Width IQ Sample:
Q:
15
Avalon-ST Data Word in AxC Container:
15-Bit Width IQ Sample:
Q:
14
31
6
larger than 24 are hypothetical; the CPRI IP core cannot implement them.
Sample/Sec)
Table
614.4 [120]
1228.8 [240]
2456.7 [480]
3072 [600]
4915.2 [960]
6144 [1200]
Figure
4–4:
Table 4–4
4–12, the maximum number of active data channels is higher in
Table 4–5
shows the correspondence between these frequency factors in
shows the correspondence between these factors in 15-bit
30
37
3.84
2.5
15
18
3
7
(1)
(1)
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