Adrv9001 In Dmr Type Portable Radio Application - Analog Devices ADRV9001 User Manual

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ADRV9001 IN DMR TYPE PORTABLE RADIO APPLICATION

ANTENNA
PA
RF SWITCH
RF I/O FUNCTIONALITY
Rx1A RF RECEPTION
Rx1B USED BY Tx INIT CALIBRATIONS
Tx1 RF TRANSMISSION
DMR Type Portable Radio Overview
ADRV9001 transceiver with minimum number of external components can be utilized to build complete RF-to-bits signal chain that can
serve as RF front end in DMR type applications. For systems that demand superior LO phase noise performance ADRV9001 allows user
to apply eternal RF LO. ADRV9001 internal AGC can be utilized to autonomously monitor and set appropriate gain level for Rx signal
chain. For time critical TDD type applications control of the ADRV9001 TRx can be done by toggling control lines. ADRV9001 can
control external Rx/Tx switch using its analog GPIOs as well as provide power amplifier bias voltage by utilizing AuxDAC outputs.
Table 6. Constrains and Limitations in DMR type Portable Radio Application
Functionality Constrains and Limitations
User have to ensure that appropriate level of isolation between Rx1 and Rx2 as well as Rx to Tx is provided at system
Rx Signal Path
level. In example above, RxB input is utilized only during initialization calibrations. The LNA connected to the Rx1A
should be powered down during Tx slots to ensure proper operation of the Tx calibration path (connected to the
Rx1B). User should ensure that appropriate attenuation is present in line to prevent Rx being overloaded by Tx signal.
LO Generation In Portable Radio, DMR type application, ADRV9001 can use its internal LO to generate RF LO1 for both uplink and
downlink. For applications with stringent RF LO requirements, user can use external LO inputs. External LO1 operating
at 2x RF LO can be used for both uplink and downlink.
RF Front End For LO generation, ADRV9001 utilize internal VCO that generates square wave type signal. A square wave LO would
produce harmonics. For example: depending of RF matching used on the RF ports user 2nd LO harmonic can be as
high as -50dBc and 3rd harmonic can be as high as -9 dBc. Therefore the RF filtering on the Rx and Tx path must
ensure that signals at the LO harmonic frequencies (up to 9th in some cases) are not affecting overall system
performance.
VGA
LPF
TEMPERATURE
SENSOR
BPF FILTER
LNA
Figure 8. ADRV9001 in DMR Type Portable Radio Application
BALUN Tx1
COUPLER
ATTENUATOR BALUN
Rx1A
BALUN
Rx1B
BALUN EXT LO1
/2
EXTERNAL
RF PLL1
LO SOURCE
BALUN EXT LO2
/2
RF PLL2
AGPIOs AuxADC
Rev. PrA | Page 20 of 253
Preliminary Technical Data
POWER IC
ADRV9001
Tx1
DATA
3/4/6/7/8/10
INT
QEC SSI
DAC
LOL
Rx1
DDC DATA
3/6/8
DEC
ADC SSI
QEC
DC
14/16
DGPIOs
2
Rx/Tx_ENABLE
GP_INT
3/4
SPI
RESET
DEV_CLKL_OUT
MCS
BALUN
DEV_CLK
AuxDAC
FPGA
OR
BBIC
VCXO