Compact Integrated Receivers UsingCustom and Commercial MMIC Technology

Matt Morgan9/7/2006

Compact Integrated Receivers

1. critical for focal plane arrays beam spacing field of view

2. lower mass more efficient cryogenics tighter temperature control reduced mechanical load

3. fewer connectors and cables greater reliability reduced VSWR effects reduced gain slopes fewer entry points for RFI

MMIC Modules are More Compact, Lightweightand Manufacturable than Conventional Assemblies

Multi-Chip Module

Assembly of IndividuallyPackaged Components

Many MMICs available Commercially

Most things below 50 GHz are available off-the-shelf for less than $50Exceptions include:

balanced port configurations non-standard impedance some wide IF-Band mixers

Some things in the 50-100 GHz range can be found in commercial productlistings, but

sparse frequency coverage usually narrow-band, targeted for specific applications

(communication and radar bands, etc.) some exotic functions not supported (compound switches, etc.)

Finally, there is a large pool of proven custom designs to draw from,designed by NRAO and our collaborators (JPL, ATA, universities,foundry IRAD designs, etc.)

Some Examples: W-Band Signal Source

2.5 cm

Some Examples: Compact Water Vapor Radiometer

All Commercial MMICs!

Some Examples: ALMA Active Multiplier Chain

Some Examples: DSN Array Ka-Band Downconverter

Working Toward an All-MMIC Receiver

1. Once a design is set, MMIC components and assemblies can be mass-produced with exceptional repeatability especially in the cm-wave range, where most MMICs are

commercially available – chips are screened by the manufacturerand their specs guaranteed.

module assembly is insensitive to small variations – bondwires are used for 50 interconnects, not for tuning!

2. Repairs are relatively easy to diagnose and repair because of the inherent uniformity in performance, device failure is

usually apparent from the DC bias alone. when it isn't, the chips are cheap enough to simply replace them one

at a time until the culprit is found.

It is therefore reasonable to think about implementing even very sophisticatedfront-ends in a single module using all MMIC technology.

no internal connectors! no internal cables! only 1 block to machine small, lightweight, manufacturable

Shall we take integration a step further:Receiver-on-a-Chip?

I would say no... LNAs, mixers, and multipliers have all been demonstrated on common

semiconductor technologies, but with compromised performance – betterto pick the right MMIC process for the right chip

even if it works, the yield is too low on III-V semiconductors for large-scaleintegration

a lot of expensive wafer real estate is wasted on passives can no longer take advantage of commercial components – have to design

it all from scratch no opportunity for chip reuse Microwave substrates are thin! A large, floppy chip would be too hard to

handle and mount without damaging it.

Could We Put the Whole Receiver in OneModule and Cool Everything?

Not if it is a heterodyne receiver, because LO generation dissipates too much power for cryogenics IF components are usually Silicon, which will not function cold

However, special-purpose direct detection receivers could occupya single cold module

even more compact better sensitivity better temperature stability better component lifetime

Another Problem: Why are those bias boards so big?

Because we put a lot on them! linear regulators potentiometers for tuning and gain

control digital logic for configuration switching

and channel selection Op-Amps for gate servo loops and

monitor points IF circuitry

It makes for a user-friendly module, butif we're serious about compactness,particularly for focal plane arrays, then wemust find a way to trim this part down.

Option #1: Develop Common Bias Blocks in Die Formor Integrated SMT Packages

Two external resistorsset the desired drainvoltage and current.

Probably very expensive!(unless we buy millions of them)

Not suitable for cooling if donein Silicon.

Option #2: Limit DC inputs to analog bias voltages

Put nothing in the block exceptbasic EMI and over-voltageprotection.

All current control, monitoring,and tuning functions can beimplemented in a central M&Cunit (more efficiently, in fact...)

Option #2: continued...

With all monitor functions in one place, some parts can be shared.

What About LNAs?

more compact easier to integrate in large

multi-function modules easy to replicate module assembly can be

done commercially

Pros

MMIC LNAs MIC LNAs

higher-Q passive components allows pre-selection of active

devices for optimumperformance

larger development cost

Cons

difficult to transfer assembly"know-how" to commercialmanufacturers.

A "Nearly Monolithic" LNA

Maybe we can compromise between optimum performance and large-scalemanufacturability by using a hand-picked first-stage discrete device followedby a MMIC.

Discrete stageMMIC stage

Case Study: Ka-Band All-MMIC Receiver

Calculated Performance: noise temperature = 10 K gain = 60 dB P1dB = -45 dBm (input) LO = 2 mW (6-9 GHz) power dissipation = 150 mW (cold part), 3.5 W (warm

part)

BPFBPF

BPF x2

26-40 GHz2-4 GHz

VelociumALH369TRW

HCA4200P

TriquintTGL-4203

VelociumALH369

Mimix BBXM1001

24-36 GHz

x2

Mimix BBXX1000

HittiteHMC205

6-9 GHz12-18 GHz

BPF

AvagoHMMC-5618

COLD MODULE WARM MODULE

BPF

26-40 GHz

VelociumALH369TRW

HCA4200P

TriquintTGL-4203

VelociumALH369

SirenzaSBB-5089

Mimix BBXM1001

Anaren11306-3

BPF

Anaren11306-3

2-4 GHz

SirenzaSBB-5089

TriquintTGL-4203

2-4 GHz

2-4 GHz

26-40 GHz

26-40 GHz

All-MMIC Cold Receiver Module

RF inputsLO input (underneath)

IF outputs

IF hybrids

MMICs

All-MMIC Cold Receiver Module

The size of a well-designed MMIC module is typicallydominated by connectors and waveguide flanges.

MMIC-Based Cold Receiver Assembly

OMT

LO IFIF

MMICModule

Bias/M&C

Cooled Focal Plane Array

Backup slides follow

If the entire receiver is cooled anyway, should we considerusing superconducting passive elements (couplers, filters, etc)?

I don't think so excellent LNA performance can be achieved at ~20K, but a good

microwave superconductor would force you to much lowertemperatures (~5K)

not really a commercial process – your passive elementscould be more expensive than the MMICs!

you lose the ability to test it at room temperature not much to gain anyway? – superconductors are not lossless

at high frequency, and cooled copper may be competitive if it isreasonably pure