Nokia RM-596 - Qubbe; Receiver (RX); Synthesizer; Transmitter (TX)

QuBBE
The front end module called QuBBE contains the needed front end filters and the switches. QuBBE contains:
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3 duplexers (Band II, V, VIII)
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1 triplexer (Band I, IV)
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12 switches with the control
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Low and high band GSM TX low bass filters
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50 ohms low and high and antenna interface
The control signals for the switches come from Älli.
Receiver (RX)
Linko RF has higher integration level compared to previous RF generations and especially more digital design
blocks have been integrated to Älli, RF Asic.
Älli contains the receiver chain from LNAs to digital base band interface. Digital RX baseband interface
contains four data and one clk signals. The data rate and clock frequency depend on the use case.
The main blocks in Älli are:
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LNAs: Balanced inputs for 850, 900, 1800, 1900, 2100 bands
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Passive mixer
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Analog baseband: Programmable for different modes
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ADC: Programmable Sigma Delta Modulator topology ADC
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RX Digital Front End (RXDFE): Contains for example digital filtering, DC offset compensation, wide/
narrowband power measurement blocks
There is integrated external LNA matching on the bands 900, 1800, 1900 and 2100. On 850 band, there is an
integrated matching.
Synthesizer
The synthesizer has separate highly integrated 4GHz VCOs for RX and TX. The integrator capacitors of the loop
filter are outside of the IC. The PLLs are fractional type of dividers.
The reference oscillator is an on-chip 38.4 MHz digitally controlled oscillator. The 38.4 MHz crystal is outside
of Älli. DCXO delivers the internal clock to Älli, differential clock signal to BB, and two single mode clock signals
to NCW modules. Älli delivers a clk signal to diversity RX. The oscillator is controlled via RFBus with AFC signal.
Temperature compensation of the oscillator is running by the SW in Älli. The temperature sensor itself is
outside of Älli.
Transmitter (TX)
The main features of Linko1 transmitter are:
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Common PA for GSM and WCDMA
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High and low band signal paths
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Low band: 824 - 915 MHz
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High band: 1710 - 1980 MHz
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Two operation modes in PA
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Saturation mode in GMSK usage
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Linear mode in Edge and WCDMA usage
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No TX filter between PA and Älli
RM-596
System Module
Issue 2 COMPANY CONFIDENTIAL Page 6 – 33
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