GP1020
TYPICAL GPS RECEIVER (Fig. 2)
All satellites use the same L1 frequency of 1575·42MHz, but different Gold codes, so a single front-end may be used. To
achieve better sky coverage it may be desirable to use more than one antenna, in which case separate front-ends will be needed.
GND
MASTER CLK
SAMPLE CLK
SIGN
MAG
V
SS
15V
V
DD
MASTERRESET
NAVIGATION
SOLUTION
GP1010
&
FILTER
MASTER/SLAVE
CS
DECODE
DATA BUS (16)
ADDR BUS (8)
CONTROL
SIGN 0
MAG 0
SIGN 1
MAG 1
GP1020
(MASTER)
TIC OUT INT OUT
MICROPROCESSOR
SYSTEM
3
MULTIPLE ANTENNAS TO GIVE
WIDER SKY COVERAGE
SLAVECLK
TIC IN
SIGN 0
MAG 0
SIGN 1
MAG 1
INT IN
OPTIONAL
SECOND
GP1010
&
FILTER
CS
DECODE
OPTIONAL SECOND
GP1020
(SLAVE)
V
SS
V
DD
MASTER/SLAVE
15V
GND
MASTERRESET
Fig. 2 GPS receiver simplified block diagram
TYPICAL GLONASS RECEIVER (Fig. 3)
Each satellite will use a different ‘L1’ carrier frequency, in the range 1602·5625 to 1615·500MHz, with 0·5625MHz spacing,
but all with the same 511-bit spreading code. The normal method for receiving these signals is to use several front-ends, perhaps
with the first LNA and mixer common, but certainly with different final local oscillators and mixers.
GLONASS FRONT-END
FILTERS, AMPLIFIERS
AND MIXERS
CHANNEL
SELECTION
AND ADC
CHANNEL
SELECTION
AND ADC
CHANNEL
SELECTION
AND ADC
CHANNEL
SELECTION
AND ADC
CHANNEL
SELECTION
AND ADC
FREQUENCY
GENERATOR
CHANNEL
SELECTION
AND ADC
SAMPLE CLK
SIGN
MAG
SIGN
MAG
SIGN
MAG
SIGN
MAG
SIGN
MAG
SIGN
MAG
GND
V
SS
15V
V
DD
MASTER/SLAVE
L-BAND
DOWN
CONVERTER
SAMP CLK
SIGN 0
MAG 0
SIGN 1
MAG 1
SIGN 2
MAG 2
SIGN 3
MAG 3
SIGN 4
MAG 4
SIGN 5
MAG 5
NAVIGATION
SOLUTION
MASTERRESET
CS
DECODE
MICROPROCESSOR
SYSTEM
DATA BUS (16)
GP1020
ADDR BUS (8)
CONTROL 3
INT OUT
MASTER
CLOCK
OSCILLATOR
FREQUENCY
SELECTION
Fig. 3 GLONASS receiver simplified block diagram
2