The.California-based.Savi.Corporation.was.founded.in.1989..It.is.predominately.involved.in.active.
RFID.systems.and.is.probably.the.market.leader.in.this.area..Savi.is.heavily.involved.in.defense.
applications.for.both.the.United.States.and.NATO.countries..Specific.applications.include.the.track- ing.of.expensive.assets.and.containers.through.logistical.systems..Savi.was.acquired.by.Lockheed.
Martin.in.2006..The.Savi.Web.site.is.www.savi.com.
7.2.1 sAvI ActIve tAgs
Most.Savi.tags.are.based.on.similar.highly.developed.active.RFID.technology..The.tags.generally.
operate.on.433.MHz.at.28.kbps..Their.range.is.approximately.200.ft.with.mobile.RFID.readers.and.
300.ft.with.fixed.readers..The.difference.in.tags.lies.mainly.in.their.intended.end.application..Their.
tags.are.categorized.as.either.asset.or.data-rich.tags..The.following.Savi.tags.are.reviewed:
•. ST-602
•. ST-604
•. ST-654
•. ST-656
7.2.1.1 SaviTag ST-602
The.small.ST-602.is.classified.as.an.asset.tag..It.is.designed.to.be.attached.to.relatively.small.inven- tory.items..It.is.2.4.×.1.7.×.0.48.in..The.tag.weighs.approximately.1.ounce..The.tag.is.powered.
by a 3.V,.540.mA.non-replaceable,.non-rechargeable.lithium-ion.battery..The.battery.life.is.listed.as.
4.years.with.10.reads.per.day..The.tag.has.16.bytes.of.memory.for.identification.and.16.bytes.
of.user.memory..The.tag.returns.the.tag.identification,.the.tag.status,.and.the.reader.identification..
The.ST-602.is.illustrated.in.Figure.7.1.
FIGURE 7.1 Savi.ST-602.
7.2.1.2 SaviTag ST-604
The.ST-604.tag.is.designed.for.users.needing.more.battery.life.than.the.ST-602..The.ST-604.is.
6.25.×.1.7.×.1.3.in..It.has.the.same.16-byte.identification.and.user.memory.as.the.ST-602..The.tag.
also.returns.the.tag.ID,.the.tag.status,.and.the.reader.ID..The.battery.life.is.much.longer.than.the.
ST-602.at.10.years,.with.10.reads.per.day..As.with.the.ST-602,.the.battery.is.non-replaceable.and.
non-rechargeable..The.ST-604.is.illustrated.in.Figure.7.2.
7.2.1.3 SaviTag ST-654
The.Savi.ST-654.is.intended.for.use.on.shipping.containers..It.is.classified.by.Savi.as.a.data-rich.tag..The.
ST-654.has.128.K.bytes.of.memory.in.comparison.to.the.ST-602’s.and.ST-604’s.16.bytes..This.allows.
the.user.a.great.deal.of.flexibility..Aside.of.the.tag.ID,.the.user.can.also.program.the.contents.of.the.
container.that.the.tag.is.attached.to..The.tag.is.similar.in.size.to.the.ST-604.at.6.25.×.2.12.×.1.125.in..
The.tag.is.also.more.sophisticated.than.the.ST-604.in.that.the.3.6.V.lithium.battery.may.be.replaced.in.
the.field.without.special.tools..However,.the.expected.battery.life.is.less.at.5.years.with.two.collections.
per.day..The.tag.also.has.a.buzzer.for.assistance.in.location..Figure.7.3.illustrates.the.ST-654.
7.2.1.4 SaviTag ST-656
The.ST-656.is.designed.to.be.used.on.large.ISO.shipping.containers..It.can.be.attached.to.the.left.door.
of.an.ISO-compliant.container..It.is.weatherproofed.in.order.to.operate.under.adverse.conditions..The.
housing.has.the.appearance.of.a.clamp.with.a.front.and.back.case..In.position,.the.tag.is.inside.of.
the.container..The.front.case.is.4.75.×.4.5.×.1.5.in..The.back.case.is.4.6.×.3.2.×.2.in..Like.the.ST-654,.
the.ST-656.utilizes.a.replaceable.3.6.V.lithium.battery..The.battery.life.is.also.the.same.at.5.years.
with.two.collections.per.day..The.battery.is.also.replaceable.without.special.tools..The.tag.also.has.a.
beeper.for.location.and.other.alarms..The.ST-656.is.illustrated.in.Figure.7.4.
7.2.2 sAvI fIxed ReAdeRs
Savi.offers.both.fixed.and.mobile.readers..In.this.section,.we.will.review.fixed.readers..The.Savi.
fixed. readers. are. intended. to. be. positioned. permanently. in. storage. yards,. terminals,. and. ware- houses..The.readers.can.be.interfaced.together.through.an.Ethernet.network.
FIGURE 7.2 Savi.ST-604.
FIGURE 7.3 Savi.ST-654.
Active RFID System Components 93
The.following.Savi.fixed.readers.will.be.reviewed:
•. SR-650
•. Savi.signposts
7.2.2.1 SR-650 Fixed Reader
The.SR-650.fixed.reader.is.a.long-range.omnidirectional.antenna/reader..Its.intended.use.is.for.asset.
inventory..The.reader.operates.on.433.MHz..It.is.compatible.with.all.Savi.active.tags..The.range.
of.the.antenna.is.100.m..The.antenna/reader.is.designed.to.be.weatherproof.with.a.polypropylene.
housing.with.UV.inhibitors..It.can.operate.between.−32°C.and.60°C..It.is.circular.in.shape.with.
a diameter.of.12.in..and.a.height.of.5.in..Figure.7.5.illustrates.the.SR-650.fixed.reader.
7.2.2.2 Savi Signpost
The.other.fixed.reader.that.Savi.offers.is.the.signpost..The.signposts.are.designed.for.use.in.dock.
portals.and.vehicle.gates.through.which.tagged.material.passes..This.prevents.unintentional.cross- reads. from. occurring,.which.might.be. possible.with.the. omnidirectional. SR-650..By.utilizing.a.
number.of.signposts,.the.RFID.system.can.positively.determine.the.location.of.the.tags..The.sign- posts.can.read.tags.traveling.as.fast.as.60.miles.per.h..The.signposts.are.available.in.short,.medium,.
and.long.range..The.model.designations.are.SP-65X-111,.SP-65X-211,.and.SP-65X-311..The.long- range.model.has.a.range.of.up.to.12.ft..Figure.7.6.illustrates.a.Savi.signpost.
FIGURE 7.4 Savi.ST-656.
FIGURE 7.5 Savi.SR-650.fixed.reader.
7.2.3 sAvI moBILe ReAdeRs
When.the.permanent.nature.of.fixed.readers.is.less.appropriate,.Savi.offers.a.mobile.solution.based.
on.the.SMR-650.antenna.reader..Readers.of.this.type.are.particularly.useful.for.commissioning.
tags..This.reader.has.a.range.of.200.ft..This.unit.interfaces.with.a.PC.through.a.DB-9.pin.RS-232.
port..The.dimensions.are.6.25.×.1.5.×.1.in..The.weight.is.6.4.ounces..The.unit.uses.a.3.7.V.420.mAh.
lithium-ion.battery..The.battery.life.is.listed.as.3–4.days.of.continuous.operation..Figure.7.7.illustrates.
the.SMR-650.antenna/reader.
The.unit.can.be.attached.to.either.the.Intermec.751.G/A.computer.or.a.conventional.notebook.
computer..A.SMR-650.attached.to.the.Intermec.751.G/A.is.illustrated.in.Figure.7.8.
FIGURE 7.6 Savi.Signpost.
FIGURE 7.7 Savi.SMR-650.antenna/reader.
FIGURE 7.8 Savi.SMR-650.attached.to.the.Intermec.751.G/A.
Active RFID System Components 95