VEGA
MCUK991001G8
Section 8
Issue 1
Technical Guide
– 31 –
Revision 0
8 VEGA
8.1 Introduction
VEGA contains the interface circuits to the Audio, RF and auxiliary analogue functions for the baseband circuit.
8.2 Functional Description
Figure 8.1: VEGA Block Diagram
8.2.1 Uplink I and Q
VEGA performs GMSK modulation on Data samples received from GEMINI at 270 kilobits per second.
Figure 8.2: Functional structure of the baseband uplink path
TIMING
JTAG
BURST
STORE
GMSK
MOD
FILTER
FILTER
DSP INTERFACE
10 bit
I DAC
8 bit
SIGMA-DELTA
RAMP DATA
SIGMA
DELTA
10 bit
DAC
SP INTERFACE
10 bit
Q DAC
8 bit
DAC
8 bit
DAC
13 bit
DAC
FILTER
FILTER
8 bit
SIGMA-DELTA
FILTER
FILTER
SIGMA
DELTA
10088-1
Timing interface
Din
270 kHz
Burst
Register
Burst Timing
Control
Differential
Encoder
Gaussian
Filter
Sine
Table
Offset
Register
Offset
Register
Low Pass
Filter
Power
Register
Ramp-up
Shaper
Integrator
8 bit DAC
To Power
control DAC
phase(i) 16 *270 kHz
Cosine
Table
Low Pass
Filter
8 bit DAC
ULIP
ULIN
ULQP
ULQN
10089-1