Configure a TD-SCDMA Waveform with Single Carrier Uplink RMC for Base Station BER Receiver Sensitivity Measurement

This example shows you how to set up the equipment and configure the N7612C Signal Studio for TD-SCDMA/HSPA 2018 software to create a single carrier uplink TD-SCDMA waveform in Advanced Capability for a typical base station BER receiver sensitivity measurement.

In this example, the N5182A MXG or E4438C ESG signal generator will be used and the Signal Studio for TD-SCDMA/HSPA software generates the waveform based on the waveform, carrier, timeslot/channel parameters configuration, then download the waveform into the signal generator.

Step 1: Setup the PC and the signal generator according to the above graphic

Step 2: Configure the Waveform

  1. Click Waveform Setup in the tree view (left pane of the main window) to configure waveform parameters. The parameter view (right pane) now displays the Carrier Configuration Summary table and the Waveform Setup section. The Waveform Setup section contains the key waveform related parameters.

  2. Add one Advanced Carrier: You have the option of adding either a Basic or Advanced carrier to the current carrier selection showing in the configuration summary table.

    1. In the configuration summary table, click the Add new carrier button .

    2. Select Advanced from the drop-down menu.

    3. Make sure you have one Advanced Carrier listed in the table.

  3. Set the waveform parameters:

    1. Waveform Name: Set the waveform name as desired. The name you define here is displayed on the signal generator when you download the waveform.

    2. Switch Point: Set to 3 for this example so that the TS4, TS5 and TS6 are downlink timeslots.

    3. Number of Frames: Set to a multiple of the number of subframes in one TTI and long enough to perform BER measurement. For example, for 40ms TTI, there are eight subframes in one TTI (one subframe is 5 ms), therefore, the number of subframes must be set to a multiple of 8. Set to 120 for this example to ensure that we have enough long waveform for BER testing.

    4. Filter: Select Root Raised Cosine, set Alpha = 0.22, Length = 64 symbol for this example. You can set other filter types as desired.

    5. Truncated PN: Set to On to use the truncated PN as transport channel input data. The purpose of the truncation is to ensure that the PN sequence repeats integer times in the waveform, providing a predictable bit pattern for the BER measurement. To get details on how the payload is truncated, see Transport Channels User Files.

    6. Payload Export: Set to On to export the channel payload data into text files, which you can use as the expected data at the receiving end to calculate the BER.

    7. Exporting Path: Select the directory to export the payload data files.

    8. Marker 1 Source: Set to Subframe to ensure the Event 1 output present the first sample point of each subframe.

    9. Leave all other parameters settings at their default values.

Step 3: Configure the Carrier (Advanced)

  1. Now you can see the Closedadvanced carrier displayed in the tree view. Click the carrier node in the tree view to set the carrier parameters. The Carrier Setup in the parameter view displays the baseband and 3GPP parameters for that carrier.

    1. SYNC-DL ID, SYNC-UL ID, Scrambling Code, Basic Midamble Code: Set the SYNC-DL ID to 0. Note that the SYNC-UL ID, Scrambling Code and Basic Midamble Code belong to the code group determined by the SYNC-DL ID and change automatically as the SYNC-DL ID changes.

    2. Leave all other parameters settings at their default values.

Step 4: Configure Channels

  1. Disable the PCCPCH Channel: Click PCCPCH in the tree view. The parameter view (right pane) now displays the Primary Common Control Channel Setup. Turn it OFF.

  2. Disable DwPTS and UpPTS: turn the state of the DwPTS and UpPTS to OFF.

  3. Add RMC Channel: Click Dedicated Channel in the tree view to configure RMC parameters. The parameter view (right pane) now displays the Dedicated Physical Channel Summary table. Add one uplink 12.2 Kbps RMC channel by clicking the Add a new physical channel button and selecting Uplink 12.2Kbps from the drop-down menu. 

  4. Configure Payload for RMC channel: Double click uplink 12.2Kbps in the summary table to enter the RMC uplink 12.2 Kbps channel setup.

    1. Set the Payload type in the Closedphysical channel to STD and leave all other parameters settings in physical channel as their default values.

    2. Set all of the Payload type in the Closedtransport channels (DCH #1 and DCH #2) to PN9.

Step 5: Configure the Resource Unit (RU) Allocation

  1. Timeslot: Set it to 1 in this example. You can also set to other timeslots if there is no resource conflicts.

  2. Channel Code: Set it to 1 in this example. You can also set to other timeslots if there is no resource conflicts.

  3. User ID: Set it to your desired value.

Step 6: Configure the Signal Generation Parameters

  1. Click Signal Generator in the tree view. The parameter view now shows seven panes: Configuration, Basic, I/Q, ALC, Dual ARB, Dual ARB Marker Utilities, Dual ARB trigger.

  2. Frequency: Under Basic Pane, set it to 2 GHz.

  3. Amplitude: Under Basic Pane, set it to -8 dBm for this example

Step 7: Generate and Download the Waveform, View Graphs

  1. Click Generate a waveform button in the tool bar. The software generates an I/Q waveform file in accordance with the current channel configuration and signal generation setup. Waveform generation time varies proportionally to the complexity of the waveform.

  2. To download the waveform file to the signal generator, click Download in the tool bar if you have configured the instrument connection.. The signal generator automatically begins to play the TD-SCDMA waveform. Local control of the signal generator is re-enabled by pressing the Local hardkey, allowing signal generator settings to be modified from the front panel. The waveform file, however, cannot be modified after downloading it to the signal generator.