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Overview
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Frequency Bands
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Frequency Range
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Duplex
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Band I
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1920 1980 MHz (uplink)
2110 2170 MHz (downlink)
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190 MHz
12 channels
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Band II
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1850 1910 MHz (uplink)
1930 1990 MHz (downlink)
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80 MHz
12 channels
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Band III
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1710 1785 MHz (uplink)
1805 1880 MHz (downlink)
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95 MHz
15 channels
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Band IV
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1710 1775 MHz (uplink)
2110 2175 MHz (downlink)
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400 MHz
12 channels
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Band V
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824 849 MHz (uplink)
869 894 MHz (downlink)
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5 channels
45 MHz
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Band VI
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830 840 MHz (uplink)
875 885 MHz (downlink)
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45 MHz
2 channels
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Band VII
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2500 2570 MHz (uplink)
2620 2690 MHz (downlink)
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120 MHz
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Band VIII
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880 915 MHz (uplink)
825 860 MHz (downlink)
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45 MHz
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Band IX
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1749.9 1784.9 MHz (uplink)
1844.9 1879.9 MHz (downlink)
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95 MHz
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Band X
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1710 1770 MHz (uplink)
2110 2170 MHz (downlink)
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400 MHz
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Channel spacing
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200 kHz
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Channel Bandwidth
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5 MHz
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Modulation
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QPSK (dl)
2*BPSK/HPSK (ul)
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Chip rate
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3.84 Mcps
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Access format
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CDMA
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Speech
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Adaptive multirate (AMR), dynamic operation on full and half rate channel depending on capacity and reception quality
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Power control
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Up to 1500 power control commands per second changing the level in increments of 1, 2 or 3 dB, depending on the setting of the Node B (base station)
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Applications
WCDMA or UMTS as it is called throughout Europe is a standard which has been developed to accommodate higher data rates of up to 2 Mbps to allow features like internet surfing, video telephony or video download. Even though WCDMA is focusing on high data rates it still supports simple features like a plain voice call or sending of SMS.
The following table lists some of the service profile, the required data rate, whether this is circuit switched or packet data and example applications:
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Service Profile
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Data rate
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Transmission method
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Example Application
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Voice
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16 kbit/s
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circuit switched
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Voice Calls
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Simple Messaging
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14,4 kbit/s
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packet data
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SMS, MMS
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Switched Data
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14,4 kbit/s
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circuit switched
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E-Mail
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High Interactive Multimedia
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max. 128 kbit/s
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packet data
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Video-Telephony
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High Interactive Multimedia
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max. 384 kbit/s
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circuit switched
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Online-Gaming
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High Multimedia
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max. 2 Mbit/s
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packet data
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Video-Streaming
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Technology in brief
WCDMA is a CDMA system. CDMA stands for code division multiple access. This means that the available frequency channel is broken down by different code sequences that are multiplied by the user signals of the individual subscribers. All subscribers transmit on the same frequency and at the same time.
For WCDMA different base stations are distinguished by a different scrambling code, which makes cell planning a lot easier, since neighboring cells can re-use the same frequency! (However, the occupied "SNR" or Signal to Noise Ratio is the limiting factor and characteristic for CDMA)
The data rate used by a terminal depends on spreading factor assigned to this particular terminal. If several terminals use the same spreading factor, the signals are distinguished through different code channels. At present the maximum data rate is 384 kbps. In the future it will be possible to combine several code channels to a multi-code link, allowing data rates up to 2 Mbps. However, when this is used the capacity of this frequency channel is used up, i.e. no other terminal can operate on this frequency channel. The reason for this is that there is no more "SNR" left for additional connections. This is the capacity issue indicated above.
In order to address higher data rates high speed downlink packet access (HSDPA) has been introduced into Release 5 of the WCDMA (3GPP) standard. HSDPA allows data rates of up to 10 Mbps (and 20 Mbps for Multiple Input Multiple Output (MIMO) systems) and is based on 16-QAM modulation. As the name suggests HSDPA is only available in the downlink direction, i.e. ideal for loading large Emails, surf the web or download videos.
Typical measurements
Transmitter Measurements:
- Maximum Output Power
- Frequency Error
- Inner Loop Power Control in the Uplink
- Minimum Output Power
- Spectrum Measurements
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- Occupied Bandwidth (OBW)
- Spectrum emission mask (SEM)
- Adjacent Channel Leakage Power Ratio (ACLR)
- Transmit Modulation
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- Error Vector Magnitude (EVM)
- Peak code domain error (PCDE)
Receiver Measurements:
- Reference Sensitivity Level
- Maximum Input Level
Willtek Test Instruments
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