Please refer to the User Guide for information on selecting the W-CDMA/HSPA+ Signal Analyzer mode, setting up frequency, amplitude, power offset for compensating external loss, limit lines, markers, and file management.
Scrambling Code Setup
The scrambling code can be set up automatically or manually.
In Auto mode, the unit automatically locks on to the strongest scrambling code in the signal. In Manual mode, the desired code is manually entered and the unit looks only for that specific scrambling code.
To set up auto scrambling:
1. Press the Setup main menu key.
2. Press the Scrambling Code submenu key to select Auto.
To manually set up a Scrambling Code:
1. Press the Setup main menu key.
2. Press the Scrambling Code submenu key to select Manual and use the keypad, the arrow keys, or the rotary knob to enter the desired Scrambling Code, as shown on the left side of the screen. Press the Enter key to set the scrambling code.
Maximum Spreading Factor Setup
In a W-CDMA system, the number of chips per data symbol is called the Spreading Factor. The lower the spreading factor the higher the data rate. According to the 3GPP standard, the spreading factor can vary from 4 to 512 and the maximum spreading factor is either 256 or 512. The instrument can be set to 256 or 512 maximum spreading factors. To set up the maximum spreading factor:
1. Press the Setup main menu key.
2. Press the Max Spreading Factor submenu key to select either 256 or 512.
S‑CCPCH Spreading Factor, S‑CCPCH Code and PICH Code Setup
In the 3GPP specification, two optional control channels are provided for S‑CCPCH and PICH. These codes can have different spreading codes and spreading factors. The S‑CCPCH spreading factor and S‑CCPCH and PICH codes can be manually entered.
Note
For the most accurate results, manually enter the S‑CCPCH spreading and S‑CCPCH and PICH codes before taking the measurement.
1. Press the Setup main menu key.
2. Press the S‑CCPCH Spread submenu key and manually enter the desired spreading factor.
3. Press the S‑CCPCH Code submenu key and manually enter the desired spreading code.
4. Press the PICH Code submenu key and manually enter the desired spreading code.
Note
The S‑CCPCH spreading factor default value is 256. The default S‑CCPCH Code is 3 and the default PICH code is 16.
Threshold Setup
The threshold level is an advanced setting that can be set to indicate which codes are considered active. In the Code Domain Power screen the threshold level is indicated by a horizontal dotted red line. Any code channels exceeding this power level are considered active traffic channels and any code channels below this power level are considered inactive or noise. The threshold level can be manually set by:
1. Press the Setup main menu key.
2. Press the Threshold submenu key and select either On or Off.
Note
Threshold can only be set in Codogram or Code Domain Power modes. The default threshold level is – 30 dB.
Filtered versus Unfiltered Power
The ACLR measurement uses the filtered channel power to determine the ACLR values and it is listed as filtered on the display. In all other screens the unfiltered channel power is displayed as channel power.