Number of antenna-carrier interfaces, Number of antenna-carrier interfaces –6 – Altera CPRI IP Core User Manual

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3–6

Chapter 3: Parameter Settings

Application Layer Parameters

CPRI MegaCore Function

December 2013

Altera Corporation

User Guide

Number of Antenna-Carrier Interfaces

The Number of antenna/carrier interfaces parameter specifies the number of
antenna-carrier interfaces, or data channels, in your CPRI IP core. The supported
values are 0 to 24. Set this parameter to the maximum number of data channels you
expect your CPRI IP core to use at the same time.

If this parameter has the value of zero, your CPRI IP core does not implement the
CPRI MAP interface. For example, you might use this option if your CPRI IP core
passes IQ data samples through the AUX interface to an external custom mapping
function that you provide. The default value of this parameter is zero.

The combination of CPRI IP core line rate, sampling width, and sampling rate restricts
the number of active antenna-carrier interfaces your CPRI IP core can support. For
example, if your CPRI IP core operates at line rate 3.072 Gbps, it can support as many
as 20 active antenna-carrier interfaces, but if your CPRI IP core operates at line rate
1.2288 Gbps, it can support a maximum of eight active antenna-carrier interfaces. For
details, refer to

Table 4–5

and

Table 4–6 on page 4–17

You can specify in software that some of the antenna-carrier interfaces that you
configure in your CPRI IP core are not active. This feature allows you to change the
number of active and enabled data channels dynamically.

The software configuration feature allows you to modify the number of active
antenna-carrier interfaces. If you modify this number, you must keep in mind the
restrictions for your current CPRI line rate. Otherwise, data is dropped in the
mapping to and from the individual antenna-carrier interfaces.

Advanced 2

Your CPRI IP core MAP interface is configured in a single AxC mapping mode only,
a mode that has the following features:

■

Conforms to Method 3: Backward Compatible described in Section 4.2.7.2.4 of
the CPRI Specification V4.2 Interface Specification.

■

Supports communication that complies with the WiMAX or LTE/E-UTRA
standard.

For information about this AxC mapping mode, refer to

Appendix D, Advanced AxC

Mapping Modes

Advanced 3

Your CPRI IP core MAP interface is configured in a single AxC mapping mode only,
a legacy mode that has the following features:

■