原标题：ADI AD9361 3G(4G)基站收发器解决方案

　　ADI公司的AD9361是面向3G和4G基站应用的高性能高集成度的射频(RF)捷变收发器(Agile Transceiver™),集成了12位ADC和DAC,支持TDD和FDD。该器件的可编程性和宽带能力使其成为多种收发器应用的理想选择。该器件集RF前端与灵活的混合信号基带部分为一体，集成频率合成器，为处理器提供可配置数字接口，从而简化设计导入.AD9361工作频率范围为70 MHz至6.0 GHz,支持的通道带宽范围为不到200 kHz至56 MHz.主要用在点对点通信系统,毫微微蜂窝/微微蜂窝/微蜂窝基站和通用无线电系统 .本文介绍了AD9361主要特性和功能框图,以及评估板AD-FMCOMMS2-EBZ主要特性和电路图以及评估板AD-FMCOMMS2-EBZ材料清单..

　　The AD9361 is a high performance, highly integrated radio frequency (RF) Agile Transceiver™ designed for use in 3G and 4G base station applications. Its programmability and wideband capability make it ideal for a broad range of transceiver applications. The device combines a RF front end with a flexible mixed-signal baseband section and integrated frequency synthesizers, simplifying design-in by providing a configurable digital interface to a processor. The AD9361 operates in the 70 MHz to 6.0 GHz range, covering most licensed and unlicensed bands. Channel bandwidths from less than 200 kHz to 56 MHz are supported.

　　The two independent direct conversion receivers have state-of-the-art noise figure and linearity. Each receive (RX) subsystem includes independent automatic gain control (AGC), dc offset correction, quadrature correction, and digital filtering, thereby eliminating the need for these functions in the digital baseband. The AD9361 also has flexible manual gain modes that can be externally controlled. Two high dynamic range ADCs per channel digitize the received I and Q signals and pass them through configurable decimation filters and 128-tap finite impulse response (FIR) filters to produce a 12-bit output signal at the appropriate sample rate.

　　The transmitters use a direct conversion architecture that achieves high modulation accuracy with ultralow noise. This transmitter design produces a best in class TX EVM of <−40 dB, allowing significant system margin for the external PA selection. The on-board transmit (TX) power monitor can be used as a power detector, enabling highly accurate TX power measurements.

　　The fully integrated phase-locked loops (PLLs) provide low power fractional-N frequency synthesis for all receive and transmit channels. Channel isolation, demanded by frequency division duplex (FDD) systems, is integrated into the design. All VCO and loop filter components are integrated.

　　The core of the AD9361 can be powered directly from a 1.3 V regulator. The IC is controlled via a standard 4-wire serial port and four real-time I/O control pins. Comprehensive power-down modes are included to minimize power consumption during normal use. The AD9361 is packaged in a 10 mm × 10 mm, 144-ball chip scale package ball grid array (CSP_BGA).

　　AD9361主要特性:

　　RF 2 × 2 transceiver with integrated 12-bit DACs and ADCs

　　Band: 70 MHz to 6.0 GHz

　　Supports TDD and FDD operation

　　Tunable channel bandwidth: <200 kHz to 56 MHz

　　Dual receivers: 6 differential or 12 single-ended inputs

　　Superior receiver sensitivity with a noise figure of 2 dB at 800 MHz local oscillator (LO)

　　RX gain control

　　Real-time monitor and control signals for manual gain

　　Independent automatic gain control

　　Dual transmitters: 4 differential outputs

　　Highly linear broadband transmitter

　　TX EVM:≤−40 dB

　　TX noise:≤−157 dBm/Hz noise floor

　　TX monitor:≥66 dB dynamic range with 1 dB accuracy

　　Integrated fractional-N synthesizers

　　2.4 Hz maximum LO step size

　　Multichip synchronization

　　CMOS/LVDS digital interface

　　AD9361应用:

　　Point to point communication systems

　　Femtocell/picocell/microcell base stations

　　General-purpose radio systems

　　图1. AD9361功能框图

　　评估板AD-FMCOMMS2-EBZ

　　The AD-FMCOMMS[234]-EBZ cards are a high-speed analog module designed to showcase the AD9361 or 9364, a high performance, highly integrated RF agile transceiver intended for use in RF applications, such as 3G and 4G base station applications and software defined radios. Its programmability and wideband capability make it ideal for a broad range of transceiver applications. The device combines an RF front end with a flexible mixed-signal baseband section and integrated frequency synthesizers, simplifying design-in by providing a configurable digital interface to a processor or FPGA. The AD9361 and AD9364 chip operates in the 70MHz to 6GHz range, covering most licensed and unlicensed bands. The boards, due to discrete external components may have less performance on some of the RF input/output connectors (for example - the FMCOMMS2 is specifically tuned to 2.4GHz). The AD9361 and AD9364 both supports channel bandwidths from less than 200kHz to 56MHz by both changing sample rate, and by changing digital filters, and decimation inside the device itself.

　　The difference between the AD9361 (2 Rx, 2 Tx) and AD9364 (1 Rx, 1 Tx) is the number of channels. Software, HDL, pinout, etc - is all exactly the same.

　　The AD-FMCOMMS2-EBZ board, in simple terms, is just the AD9361 in a 2 x 2 RF configuration. Hence the features and capabilities of the device extends to the board. The board includes a narrow tuning range balun, which is performance optimized for 2.4GHz, and provides datasheet specifications.

　　The AD-FMCOMMS3-EBZ board, in simple terms, is just the AD9361 in a 2 x 2 RF configuration. Hence the features and capabilities of the device extends to the board. The board includes a wide tuning range balun, which gets close to datasheet specifications.

　　The AD-FMCOMMS4-EBZ board, in simple terms, is just the AD9364 in a 1 x 1 RF configuration. Hence the features and capabilities of the device extends to the board. The board includes both a narrow and wide tuning range balun on a multiplexed input/output.

　　评估板AD-FMCOMMS2-EBZ 应用:

　　Wireless communications demonstration and learning tool

　　Remote radio head

　　Software-defined radio

　　Satellite modems

　　Test and measurement equipment

　　Radar and advanced imaging

　　General purpose data acquisition

　　Specifications & Features

　　General purpose design suitable for any application

　　Software tunable across wide frequency range (70MHz to 6GHz)

　　Less than 200kHz to 56MHz channel bandwidth

　　Powered from single FMC connector

　　Supports MIMO radio, with less than 1 sample sync on both ADC and DAC

　　Includes schematics, layout, BOM, HDL, Linux drivers and application software

　　Supports add on cards for spectrum specific designs (PA, LNA etc)

　　SPI access for all device registers

　　图2. 评估板AD-FMCOMMS2-EBZ外形图