Adrv9001 In A Dmr Type Portable Radio Application - Analog Devices ADRV9005 Reference Manual

Reference Manual
ADRV9001 EXAMPLE USE CASES

ADRV9001 IN A DMR TYPE PORTABLE RADIO APPLICATION

DMR Type Portable Radio Overview
With a minimum number of external components, the ADRV9001 transceiver can be used to build a 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, the ADRV9001 allows users
to apply external RF LO. The ADRV9001 internal AGC can be used to autonomously monitor and set the appropriate gain level for the receiver
signal chain. For time-critical TDD type applications, the ADRV9001 transceiver can be controlled by toggling control lines. The ADRV9001 can
control the external receiver/transmitter switch using its analog GPIOs as well as provide power amplifier bias voltage using AuxDAC outputs.
Table 7. Constraints and Limitations in a DMR Type Portable Radio Application
Functionality Constraints and Limitations
Receiver Signal Path Ensure an appropriate level of isolation between Rx1 and Rx2 as well as receiver to transmitter at the system level. In the example, RxB input
is used during initialization and tracking calibrations. The LNA connected to the Rx1A must be powered down during transmitter slots for proper
operation of the transmitter calibration path (connected to the Rx1B). Ensure that appropriate attenuation is present in the line to prevent receiver
being overloaded by the transmitter signal.
LO Generation In a portable radio, DMR type application, the ADRV9001 can use its internal LO to generate RF LO1 for both uplink and downlink. For
applications with stringent RF LO requirements, use external LO inputs.
RF Front End For LO generation, the ADRV9001 uses internal VCO that generates a square wave type signal. A square wave LO produces harmonics. For
example, depending on RF matching used on the RF ports, the second LO harmonic can be as high as −50 dBc, and the third harmonic can be
as high as −9 dBc. Therefore, the RF filtering on the receiver and transmitter path must ensure that signals at the LO harmonic frequencies (up to
ninth in some cases) do not affect overall system performance.
DPD The DPD functionality is not available when the ADRV9001 operates in the 1T1R mode.
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Figure 8. ADRV9001 in a DMR Type Portable Radio Application
ADRV9001
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