基于ADMV101424的宽带微波下变频器设计

ADI公司的ADMV1014是采用硅锗(SiGe)设计的宽带微波下变频器,针对点到点微波无线电设计进行优化,工作频率范围为 24.5-43.5 GHz.它提供两种频率转换模式.能够从正交解调直接变频为基带IQ 输出信号,并从镜像抑制下变频为复中频输出载波频率.基带输出可采用直流耦合,或更典型的是,IQ 输出将使用足够低的高通转折频率进行交流耦合,以确保充足的解调精度.SPI 接口可对正交相位进行微调,使用户能够优化 IQ 解调性能.高度集成的ADMV1013微波上变频器和ADMV1014微波下变频器非常适用于工作在28 GHz和39 GHz 5G无线基础设施频带下的微波无线电平台.这些转换器具有1GHz带宽,以及OIP3高于20 dBm的上变频器,可以支持严苛的调制方案（如1024QAM）,可支持多Gb无线数据.此外,该芯片组也支持其他应用如卫星和地面接收站宽带通信链路,航空无线电,RF测试设备和雷达系统.其卓越的线性度和镜像抑制性能尤其适合提升微波收发器范围.本文介绍了ADMV1014主要特性,功能框图以及评估板ADMV1014-EVALZ主要特性,配置图,实验室I/Q模式和IF模式配置图,电路图,材料清单和PCB设计图.

The ADMV1014 is a silicon germanium (SiGe), wideband, microwave downconverter optimized for point to point microwave radio designs operating in the 24 GHz to 44 GHz frequency range.

The downconverter offers two modes of frequency translation. The device is capable of direct quadrature demodulation to baseband inphase (I)/quadrature (Q) output signals, as well as image rejection downconversion to a complex intermediate frequency (IF) output carrier frequency. The baseband outputs can be dc-coupled, or, more typically, the I/Q outputs are ac-coupled with a sufficiently low high-pass corner frequency to ensure adequate demodulation accuracy. The serial port interface (SPI) allows fine adjustment of the quadrature phase to allow the user to optimize I/Q demodulation performance. Alternatively, the baseband I/Q outputs can be disabled, and the I/Q signals can be passed through an on-chip active balun to provide two single-ended complex IF outputs anywhere between 800 MHz and 6000 MHz. When used as an image rejecting downconverter, the unwanted image term is typically suppressed to better than 30 dBc below the wanted sideband. The ADMV1014 offers a flexible local oscillator (LO) system, including a frequency quadruple option allowing up to a 41 GHz range of LO input frequencies to cover a radio frequency (RF) input range as wide as 24 GHz to 44 GHz. A square law power detector is provided to allow monitoring of the power levels at the mixer inputs. The detector output provides closed-loop control of the RF input variable attenuator through an external op amp error integrator circuit option.

The ADMV1014 downconverter comes in a compact, thermally enhanced, 5 mm × 5 mm LGA package. The ADMV1014 operates over the −40℃ to +85℃ case temperature range.

ADMV1014主要特性:

Wideband RF input frequency range: 24 GHz to 44 GHz
2 downconversion modes
Direct conversion from RF to baseband I/Q
Image rejecting downconversion to complex IF
LO input frequency range: 5.4 GHz to 10.25 GHz
LO quadrupler for up to 41 GHz
Matched 50 Ω, single-ended RF input, and complex IF outputs
Option between matched 100 Ω balanced or 50 Ω single-ended LO inputs
100 Ω balanced baseband I/Q output impedance with adjustable output common-mode voltage level
Image rejection optimization
Square law power detector for setting mixer input power
Variable attenuator for receiver power control
Programmable via a 4-wire SPI interface
32-terminal, 5 mm×5 mm LGA package

ADMV1014应用:

Point to point microwave radios
Radar, electronic warfare systems
Instrumentation, automatic test equipment(ATE)
 

图1.ADMV1014功能框图

评估板ADMV1014-EVALZ

Evaluating the ADMV1014 24.5 GHz to 43.5 GHz, Wideband Downconverter　

The ADMV1014 is a silicon germanium (SiGe) design, wideband, microwave downconverter optimized for point to point microwave radio designs operating in the 24.5 GHz to 43.5 GHz frequency range.

The downconverter offers two modes of frequency translation. The device is capable of direct quadrature demodulation to baseband I/Q output signals, as well as image rejection downconversion to a complex intermediate frequency (IF) output carrier frequency. The baseband outputs can be dc-coupled. More typically, the I/Q outputs are ac-coupled with a sufficiently low high-pass corner frequency to ensure adequate demodulation accuracy. The serial port interface (SPI) allows fine adjustment of the quadrature phase to allow the user to optimize I/Q demodulation performance. Alternatively, the baseband I/Q outputs can be disabled, and the I/Q signals can be passed through an on-chip active balun to provide two single-ended, quadrature, complex IF outputs between 800 MHz and 6000 MHz. When used as an image rejecting downconverter, the unwanted image term is typically suppressed to better than 30 dBc below the desired sideband.

The ADMV1014 offers a flexible local oscillator (LO) system, including a frequency quadruple option allowing a range of LO frequencies from 21.6 GHz to 41 GHz to cover a radio frequency (RF) input range as wide as 24.5 GHz to 44 GHz. A square law power detector is provided to allow monitoring of the power levels at the mixer inputs. The detector output can be used to provide closed-loop control of the RF input variable attenuator through an external op-amp error integrator circuit.

The ADMV1014 downconverter comes in a compact, thermally enhanced, 5 mm × 5 mm flip chip CSP package. The ADMV1014 operates over the −40°C to +85°C case temperature range.

The ADMV1014-EVALZ evaluation board incorporates the ADMV1014 with a microcontroller, low dropout (LDO) regulators, and nanoDAC® to allow quick and easy evaluation of the ADMV1014. The microcontroller allows the user to configure the ADMV1014 register map through the ACE software. The LDO regulators allow the ADMV1014 to be powered on by a single supply and offer good power supply ripple rejection. The nanoDAC allows the user to attenuate the RF power going into the mixer of ADMV1014 without using an external power supply.

For full details on the ADMV1014, see the ADMV1014 data sheet, which must be consulted in conjunction with this ADMV1014-EVALZ evaluation board user guide when using this evaluation board.

评估板ADMV1014-EVA主要特性:

Full featured evaluation board for the ADMV1014
On-board USB for SPI control
5 V operation
ACE software interface for SPI control

图2.评估板ADMV1014-EVALZ外形图

图3.评估板ADMV1014-EVALZ配置图

图4.评估板ADMV1014-EVALZ顶视图

图5.评估板ADMV1014-EVALZ实验室I/Q模式配置图

图6.评估板ADMV1014-EVALZ实验室IF模式配置图

图7.评估板ADMV1014-EVALZ电路图:ADMV1014连接

图8.评估板ADMV1014-EVALZ电路图:MCU和电平转移连接

图9.评估板ADMV1014-EVALZ电路图:LDO稳压器连接
评估板ADMV1014-EVALZ材料清单:

图10.评估板ADMV1014-EVA设计图:左:顶层;右:底层

图11.评估板ADMV1014-EVA PCB设计图:顶层

图12.评估板ADMV1014-EVA PCB设计图:第二层电压

图13.评估板ADMV1014-EVA PCB设计图:第三层

图14.评估板ADMV1014-EVA PCB设计图:底层