Downlink Dual Carrier

DLDC Assignment Types

Any changes to the connection state, the DLDC state or the PDTCH parameters in the test set may result in the mobile receiving an assignment message (e.g. Packet Uplink/Downlink Assignment) with updated ASSIGNMENT TYPE IE field and CARRIER ID IE field, indicating that the assignment is an `Assignment on single carrier only', `Dual Carrier Assignment' or `Modification of existing assignment' by carrier ID.

The following table outlines the Assignment Type and Carrier ID that included in the assignment message associated with the actions.

Note: PDTCH1 specifies PDTCH resource on `Carrier ID 0' and PDTCH2 specifies PDTCH resource on `Carrier ID 1'.

DLDC Uplink Carrier Control

When DLDC is enabled, the Assigned DLDC Uplink Carrier(s) parameter allows configuration of which PDCH carriers are assigned to the DUT during uplink TBF establishment/reassignment (therefore specifying which carrier(s) the DUT must monitor for USF allocation). When this parameter is set to `PDTCH 2' and Downlink Dual Carrier state is enabled, if an uplink TBF is established the assignment parameters shall be those associated with PDTCH2; when this parameter is set to `Both' the Allocated DLDC Uplink Carrier parameter further qualifies which of the assigned uplink PDCH carriers is currently being granted a USF.

Due to the limitation of receiver in the test set, when the Allocated DLDC Uplink Carrier is modified during uplink TBF transfer where both DLDC carriers are assigned, there shall be a short (transient) period of time where USFs are not allocated to the DUT (during which the uplink channels are reconfigured within the test set),it requires several frames to perform.

Note: when a DUT is polled, the DUT will respond to the poll on the carrier on which the block specifying a poll response was received. If the currently allocated uplink carrier is changed before an outstanding poll response has been received, the poll response shall be lost.

Constrains on PDTCH Configuration

When setting the PDTCH configuration for DLDC Configuration, the following overriding restrictions apply:

• The PDTCH Traffic Band value must be the same as BCH Band Value. The deferred PDTCH Traffic Band value must be the same as the current BCH Band value.
• For the PDTCH1, the Supported Multislot Classes is applied. However due to hardware constraint, the maximum downlink or uplink timeslots on PDTCH2 can NOT exceed 5, the sum of the downlink an uplink timeslots on PDTCH2 can NOT exceed 7, the combined sum of downlinks can NOT exceed 10.

• The frequency of the PDTCH1 and PDTCH2 can NOT be the same at any given TDMA frame, details as follows:

  1. If both of the PDTCHs are in a frequency hopped configuration, you are only permit to configure MAIO and hopping state of PDTCH2, the MA table value and HSN are configured derived from those parameters of the PDTCH1 automatically.

  2. If only one of the PDTCHs is in a frequency hopped configuration, the MA table value is NOT allowed to include the ARFCH used by the non-hopped PDTCH.

  3. If both PDTCHs are non-hopped, they must use different Traffic ARFCNs.

Configurable Parameters

The DLDC settings are as shown in the table below:

How to set the DLDC mode?

The following procedure details how to access and configure the DLDC mode.

1. Press CALL SETUP .
2. Press the More key on the lower right corner to display the PDTCH parms (3 of 3).
3. Press DLDC Mode ( F8 ) to display the DLDC Setup menu. Use the knob to select the parameter that you want to set.

Operating Considerations

The DLDC mode is only available in the Active Cell(EGPRS) and EGPRS BCH+PDTCH operating mode. However, parameters associated with DLDC can be changed in other operating modes, but do not effect the test set's operation until the operating mode is changed to the above values.

When the DLDC mode is enabled, performing the following measurements when the data connection type is ETSI-B or SRB loopback will result in the measurement returning an `Unsupported Configuration' integrity indicator value:

• GPRS Bit Error Measurement
• Block Error Measurement (when `ETSI B Ack Measurement Mode' is set to `Loopback')
• EGPRS SRB Bit Error Measurement

Continuous Timing Advance restrictions: Due to hardware limitations, when a dual carrier configuration (i.e. two different PDCH carriers assigned) is currently in use and the allocated(i.e. demodulated) uplink carrier is set to PDCH carrier 2, it will not be possible to demodulate the PTCCH/U on PDCH carrier 1, then test set shall implicitly ignore the lack of PTCCH/U bursts (also timeout warnings) and transmit the PTCCH/D as normal. the PTCCH/D shall still be received as part of the continuous timing advance procedure correctly, but the test set will not be able to discern (or report) whether the MS correctly transmitted RACH bursts on the PTCCH/U

Related Topics

TTI Mode Configuration