基于ADMV101424的寬帶微波下變頻器設(shè)計(jì)

ADI公司的ADMV1014是采用硅鍺(SiGe)設(shè)計(jì)的寬帶微波下變頻器,針對(duì)點(diǎn)到點(diǎn)微波無(wú)線電設(shè)計(jì)進(jìn)行優(yōu)化,工作頻率范圍為 24.5-43.5 GHz.它提供兩種頻率轉(zhuǎn)換模式.能夠從正交解調(diào)直接變頻為基帶IQ 輸出信號(hào),并從鏡像抑制下變頻為復(fù)中頻輸出載波頻率.基帶輸出可采用直流耦合,或更典型的是,IQ 輸出將使用足夠低的高通轉(zhuǎn)折頻率進(jìn)行交流耦合,以確保充足的解調(diào)精度.SPI 接口可對(duì)正交相位進(jìn)行微調(diào),使用戶能夠優(yōu)化 IQ 解調(diào)性能.高度集成的ADMV1013微波上變頻器和ADMV1014微波下變頻器非常適用于工作在28 GHz和39 GHz 5G無(wú)線基礎(chǔ)設(shè)施頻帶下的微波無(wú)線電平臺(tái).這些轉(zhuǎn)換器具有1GHz帶寬,以及OIP3高于20 dBm的上變頻器,可以支持嚴(yán)苛的調(diào)制方案（如1024QAM）,可支持多Gb無(wú)線數(shù)據(jù).此外,該芯片組也支持其他應(yīng)用如衛(wèi)星和地面接收站寬帶通信鏈路,航空無(wú)線電,RF測(cè)試設(shè)備和雷達(dá)系統(tǒng).其卓越的線性度和鏡像抑制性能尤其適合提升微波收發(fā)器范圍.本文介紹了ADMV1014主要特性,功能框圖以及評(píng)估板ADMV1014-EVALZ主要特性,配置圖,實(shí)驗(yàn)室I/Q模式和IF模式配置圖,電路圖,材料清單和PCB設(shè)計(jì)圖.

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應(yīng)用:

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

圖1.ADMV1014功能框圖

評(píng)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.

評(píng)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