Analog Devices: CN0243 Reference Design for High Dynamic Range RF Transmitter Signal Chain

atomar — Sun, 27 Oct 2013 05:57:24 GMT

Current Revision posted to Documents by atomar on 10/27/2013 5:57:24 AM

BUY NOWBUY NOW

Development Tools

Kit Overview

The combination of the ADRF6702ADRF6702 IQ modulator and the AD9122AD9122 16-bit dual 1.2 GSPS TxDAC has the dynamic range necessary for a modern high level QAM or OFDM based wireless transmitter. The dynamic range of this circuit (EVAL-CN0243-EB1ZEVAL-CN0243-EB1Z) is good enough to enable both ZIF (zero IF/ baseband) and CIF (complex IF up to 200 MHz to 300 MHz). The AD9122 has the option of up to 8× interpolation, as well as a 32-bit NCO for very fine IF frequency selectivity.

The ADRF6702ADRF6702 includes an on-board fractional PLL for LO generation so that a low frequency reference (typically less than 100 MHz) is all that is necessary to synthesize the IQ modulator LO. Using the PLL in the AD9516-4BCPZAD9516-4BCPZ clock generator allows a single reference to generate both the DAC sample clock and the PLL reference for the ADRF6702.

The circuit was built using the AD9516-0AD9516-0, but other members of the AD9516-4BCPZAD9516-4BCPZ family could be used depending on the desired internal VCO frequency.

The ADRF6702ADRF6702 IQ modulator is a unique device in several respects. In addition to its exceptional dynamic range, it also includes a fractional-N PLL, which allows programming of discrete LO frequency steps of less than 25 kHz while at the same time keeping the overall frequency multiplication small enough to avoid a large increase in phase noise from the reference to the synthesizer output.

Key Applications: Communications

More Development Kits and Tools
	More Analog Devices Analog Development Kits		Analog Devices MCU based Development Kits
	Development Platforms & Kits		element14 Knode

Developement Tools

Hardware Tools

5 V power supply
Low phase noise reference source (10 MHz to 200 MHz range @ +3 dBm), Rohde & Schwarz SMA100, low noise option, or equivalent
DPG2 Digital Pattern Generator from Analog Devices
High dynamic range spectrum analyzer, Agilent E4440A or equivalent
Analog Devices EVAL-ADF4XXXZ USB Adapter

Software Tools

DPG2 Software (included with DPG)
ADRF6702 software

Technical Documents

Learning Center

Type	Description
User Guide	ADI: User Guide (CN-0243) for High Dynamic Range RF Transmitter Signal Chain Using Single External Frequency Reference for DAC Sample Clock and IQ Modulator
Datasheet	ADI: Datasheet for ADRF6702 1200 MHz to 2400 MHz Quadrature Modulator with 1550 MHz to 2150 MHz Frac-N PLL and Integrated VCO (Rev B)
Datasheet	ADI: Datasheet for AD9122 - Dual, 16-Bit, 1230 MSPS, TxDAC+ Digital-to-Analog Converter (Rev B, 05/2011)
Datasheet	ADI: Datasheet for AD9516-0 - 14-Output Clock Generator with Integrated 2.8 GHz VCO (Rev C, 02/2013)
Application Note	ADI: Application Note (AN-1100) for Wireless Transmitter IQ Balance and Sideband Suppression

Design Elements

Type	Description
Schematics	ADI: Schematics File for EVAL-CN0243-EB1Z
Layout	ADI: Layout File for EVAL-CN0243-EB1Z
BOM	ADI: BOM File for EVAL-CN0243-EB1Z
Simulation Model	ADI: IBIS Model for AD9122

Video

Kit Features

Key Feature for ADRF6702ADRF6702 are as below:

IQ modulator with integrated fractional-N PLL
Output frequency range: 1200 MHz to 2400 MHz
Internal LO frequency range: 1550 MHz to 2150 MHz
Output P1dB: 13.1 dBm @ 2140 MHz
Output IP3: 29.1 dBm @ 2140 MHz
Noise floor: −159.6 dBm/Hz @ 1960 MHz
Baseband bandwidth: 750 MHz (3 dB)
SPI serial interface for PLL programming
Integrated LDOs and LO buffer
Power supply: 5 V/240 mA

Key features for AD9122AD9122 are as below:

Flexible LVDS interface allows word, byte, or nibble load
Single-carrier W-CDMA ACLR = 82 dBc at 122.88 MHz IF
Analog output: adjustable 8.7 mA to 31.7 mA, RL = 25 Ω to 50 Ω
Integrated 2×/4×/8× interpolator/complex modulator allows
carrier placement anywhere in the DAC bandwidth Gain, dc offset, and phase adjustment for sideband suppression
Multiple chip synchronization interfaces High performance, low noise PLL clock multiplier
Digital inverse sinc filter Low power: 1.5 W at 1.2 GSPS, 800 mW at 500 MSPS, full operating conditions

Kit Contents

The Analog Devices EVAL-CN0243-EB1ZEVAL-CN0243-EB1Z is supplied with below contents:

Evaluation Board

Tags: eval-cn0243-eb1z, ad9516, ad9122, adrf6702, ad9516-0, analog_devices