Config Layer Mappings... (5G NR/5G-Advanced)

The PxSCH Layer Mappings dialog provides parameters to map active DMRS Ports or layers to input channels and for importing user-provided [H] matrix information for the input channels used by each DMRS port/layer. This configuration is performed individually for each user (PxSCH).

Carrier/Pxsch Settings

Many of the Carrier/Pxsch Settings are identical to the settings in the PDSCH Physical Downlink Shared Channel and PUSCH panels. They are replicated here for convenience.

Measurement Channels - Indicates the maximum number of input channels available for measurement configured in the Input > Channels menu.

Carrier Channels - Indicates the active input channels per component carrier (CC) configured in the Input & Antenna tab.

DMRS Ports - Specifies the active DMRS ports/layers to be mapped onto the active input channels.

RA 1) Random Access, or 2) Receiver Address Type - See PDSCH RA Type or PUSCH RA Type.

RB Offset - See PDSCH RB Offset or PUSCH RB Offset.

RB Number - See PDSCH RB Number or PUSCH RB Number.

RA Configuration - See PDSCH RA Configuration or PUSCH RA Configuration.

RBG Size [P] - See PDSCH RBG Size [P] or PUSCH RBG Size [P].

Allocated RBGs - See PDSCH Allocated RBGs or PUSCH Allocated RBGs.

PRB Bundles - The number of PRB Bundles is calculated based on the RB Number, PRB Bundle Size and RA Type.

PRB Bundle Size - See PDSCH PRB Bundle Size. For PUSCH, PRB Bludle size is always set to Wideband.

User Defined PRB Bundle Size - See PDSCH User Defined PRB Bundle Size.

Auto Channels - Determines whether the active DMRS ports/layers are mapped to carrier channels automatically or manually.

Enabled: (default) Each DMRS port/layer is mapped to all carrier channels configured under the Input & Antenna tab.

Disabled: The Channels fields in the Layer Mappings table is enabled to manually enter the carrier channel(s) used by each DMRS port/layer.

Autodetect H Matrix - Determines whether [H] matrix values are automatically detected for all users or imported as a separate [H] matrix for each user.

Enabled: (default) This setting may be best for performing tests from a base station point of view.

VSA test point is the output of a device under test (ex. 64 channel O-RUs) covering multiple users.

Auto detect beam weights/peaks/patterns and performs multi-user demod measurements.

Interference between users is estimated and compensated providing optimum EVM Error vector magnitude (EVM): A quality metric in digital communication systems. See the EVM metric in the Error Summary Table topic in each demodulator for more information on how EVM is calculated for that modulation format..

Disabled: The H Matrix and Load H Matrix fields in the Layer Mappings table is enabled to import a separate [H] matrix for the channels used by each DMRS port/layer. This setting may be best for performing tests from a UE User Equipment (e.g. cell phone) point of view.

User provides an [H] matrix for each user. [H] only reflects the channel experienced by a specific user.

VSA applies spatial filtering by applying [H] to each user.

Interference between users is not estimated/compensated. The test is from UE point of view. EVM performance will be impacted based on interference level between beams/users.

Layer Mappings

ID - Displays the ID of this layer. Each Pxsch Layer Mapping in a group must have a unique ID.

Range - 0 to 7

DMRS Port - Displays the DMRS port/layer that is mapped to the specified carrier channels.

Range: 0 o 23

Channels - When enabled (Auto Channels = unchecked), you can manually enter the carrier channels used by each DMRS port/layer. The channels entered must be valid for the specified Carrier Channels. Click Apply after configuring channels for all layers. The resulting ports and channels will be displayed in the DMRS MIMO Info Table and Beam Weights Table.

H Matrix - When enabled (Autodetect H Matrix = unchecked), this column displays the imported [H] matrix for each DMRS port/layer. For example, if PDSCH has 273 RBs with a PRB bundle size of 1 and two layers (DMRS port 0 and DMRS port 1), and each DMRS port is mapped to 64 channels, the [H] matrix for DMRS port 0 will have a size of 64x273 complex values (I, Q). Similarly, the [H] matrix for DMRS port 1 will also be 64x273 complex values (I, Q). If PRB bundle size is wideband, the [H] matrix size for each DMRS port will be 64x1 complex values (I, Q).

Load H Matrix - When enabled (Autodetect H Matrix = unchecked), click the Import... button to select the [H] matrix for the channels used by each DMRS port/layer.