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Chapter 17
W-CDMA Downlink Digital Modulation for Receiver Test
Transmit Diversity Overview
Transmit Diversity Overview
Transmit diversity is used to diminish the effects of fading by transmitting the same information from two
different antennas. However the data from the second antenna (antenna two) is encoded differently to
distinguish it from the primary antenna (antenna one). The user equipment (UE) must be able to recognize
that the information is coming from two different locations and properly decode the data.
The ESG gives you the ability to perform open-loop transmit diversity testing on UEs. This involves using
two ESGs, one setup as antenna one (non-diversity antenna) and the other configured as antenna two
(diversity antenna).
The implementation of transmit diversity in the ESG follows the 3GPP specifications and employs space
time transmit diversity (STTD) encoding on the primary common control physical channel (P-CCPCH),
page indicator channel (PICH), and the dedicated physical channel (DPCH). The synchronization channel
(SCH) uses time switched transmit diversity (TSTD). The ESG gives you the option of disabling the TSTD
mode for the SCH. The transmit diversity display for the ESG is shown in
.
Figure 17-7
ESG Transmit Diversity Selection Display
While the common pilot channel (CPICH) is not STTD encoded, it is affected when transmit diversity is
utilized. The CPICH is transmitted from both antennas (ESGs), but the pre-defined bit sequence for the
CPICH will differ between antenna one and antenna two per the 3GPP specifications.
While STTD encoding transmits the same information through both antennas, the data on antenna two is
transmitted in a different order and some bits are inverted. This is shown in
.
Antenna Selection–TSTD
Antenna Selection–TSTD
is not Active for the SCH on
Transmit Diversity Mode Selection
Selection when Tx Diversity
is not used
is Active for the SCH
the Selected Antenna
Содержание E4428C
Страница 22: ...Contents xxii ...
Страница 107: ...Chapter 3 83 Basic Operation Using Security Functions Figure 3 6 ESG Screen with Secure Display Activated ...
Страница 182: ...158 Chapter 4 Basic Digital Operation Using Waveform Clipping Figure 4 22 Rectangular Clipping ...
Страница 183: ...Chapter 4 159 Basic Digital Operation Using Waveform Clipping Figure 4 23 Reduction of Peak to Average Power ...
Страница 224: ...200 Chapter 4 Basic Digital Operation Creating and Using Bit Files ...
Страница 228: ...204 Chapter 5 AWGN Waveform Generator Configuring the AWGN Generator ...
Страница 229: ...205 6 Analog Modulation ...
Страница 276: ...252 Chapter 7 Digital Signal Interface Module Operating the N5102A Module in Input Mode ...
Страница 286: ...262 Chapter 8 Bluetooth Signals Turning On a Bluetooth Signal ...
Страница 287: ...263 9 BERT This feature is available only in E4438C ESG Vector Signal Generators with Option 001 601or 002 602 ...
Страница 330: ...306 Chapter 9 BERT Verifying BERT Operation ...
Страница 366: ...342 Chapter 10 CDMA Digital Modulation IS 95A Modulation ...
Страница 394: ...370 Chapter 12 Multitone Waveform Generator Applying Changes to an Active Multitone Signal ...
Страница 454: ...430 Chapter 15 W CDMA Digital Modulation for Component Test W CDMA Concepts Figure 15 9 Uplink Channel Structure ...
Страница 468: ...444 Chapter 15 W CDMA Digital Modulation for Component Test W CDMA Frame Structures ...
Страница 667: ...643 18 Troubleshooting ...
Страница 700: ...Index 676 Index ...