HSDPA Block Error Ratio Measurement Description

HSDPA Block Error Ratio Measurement Description

Last updated: October 19, 2012

This section is only applicable to the lab application or a test application with the required feature license.

How is an HSDPA Block Error Ratio Measurement Made?

The HSDPA block error ratio (BLER) measurement can only be performed on a Radio Bearer Test Mode connection with a Channel Type of 12.2k RMC + HSDPA or 12.2k RMC + HSPA. To perform the HSDPA BLER measurement, the test set sends blocks of data to the UE on the downlink HS-PDSCH(s). The data sent on the downlink HS-PDSCH(s) is determined by the HS-DSCH Data Pattern setting (or FDD Test "HS-DSCH Data Pattern" in FDD Test Operating Mode ). The test set then monitors the positive acknowledgments (ACKs) and negative acknowledgments (NACKs) sent by the UE on the uplink HS-DPCCH.

The UE is required to respond to every block of data directed to it with either an ACK or NACK. If it does not respond to a block in its assigned TTI, the test set logs the event as a statistical DTX (statDTX). Also, if the UE responds to a block with data other than all 1s (ACK) or all 0s (NACK), the TTI is treated as a statDTX. StatDTXs are considered block errors, and are included in the BLER calculation. You can specify how the test set responds to statDTXs using the statDTX Reception Behavior setting.

In addition to ACK/NACK information, the uplink HS-DPCCH also carries channel quality indicator (CQI) information. The test set analyzes the CQI values sent by the UE and reports the Median CQI .

Dual Cell HSDPA Considerations

When DC-HSDPA is active, there are three sets of the HSDPA block error ratio results: One for the serving cell, one for the secondary serving cell and one for the combined serving cells.

FDD Test Mode Considerations

In FDD Test operating mode the test set does not provide radio bearer setup control of the UE. You must configure the UE to synchronize to the test set, demodulate the downlink HS-SCCH and HS-PDSCH channels and generate the appropriate uplink HS-DPCCH (see Synchronizing the UE to the Test Set's Downlink to Make Measurements ).

Once the UE begins transmitting its HS-DPCCH, the test set requires a finite amount of time to acquire and decode the UE's signal. If you initiate the HSDPA BLER measurement while the test set is still acquiring the UE's signal, the measurement will report statDTXs until it finishes its acquisition and begins demodulating the HS-DPCCH. To avoid an incorrect HBLER result, it is recommended that you wait approximately 2 seconds after the UE begins transmission of its HS-DPCCH before initiating the HBLER measurement (the amount of time required varies depending upon your test configuration).

HSDPA Block Error Ratio Measurement Parameters

The trigger source for this measurement is always protocol-based (see Trigger Source Description ).

HSDPA Block Error Ratio Measurement Results

HSDPA Block Error Ratio Measurement Input Signal Requirements

Related Topics

Manual Operation: How Do I Make an HSDPA Block Error Ratio Measurement?

Programming an HSDPA Block Error Ratio Measurement

HSDPA Block Error Ratio Troubleshooting

HSDPA Counters

DC-HSDPA Counters

Block Error Ratio (BLER) Measurement Description

What 3GPP W-CDMA/HSPA Conformance Tests Are Supported?