Electronics World articles Popular Electronics articles QST articles Radio & TV News articles Radio-Craft articles Radio-Electronics articles Short Wave Craft articles Wireless World articles Google Search of RF Cafe website Sitemap Electronics Equations Mathematics Equations Equations physics Manufacturers & distributors LinkedIn Crosswords Engineering Humor Kirt's Cogitations RF Engineering Quizzes Notable Quotes Calculators Education Engineering Magazine Articles Engineering software RF Cafe Archives Magazine Sponsor RF Cafe Sponsor Links Saturday Evening Post NEETS EW Radar Handbook Microwave Museum About RF Cafe Aegis Power Systems Alliance Test Equipment Centric RF Empower RF ISOTEC Reactel RF Connector Technology San Francisco Circuits Anritsu Amplifier Solutions Anatech Electronics Axiom Test Equipment Conduct RF Copper Mountain Technologies Exodus Advanced Communications Innovative Power Products KR Filters LadyBug Technologies Rigol TotalTemp Technologies Werbel Microwave Windfreak Technologies Wireless Telecom Group Withwave RF Cafe Software Resources Vintage Magazines RF Cafe Software WhoIs entry for RF Cafe.com Thank you for visiting RF Cafe!


LadyBug RF Power Sensors

RF Cascade Workbook 2018 by RF Cafe

Please Support RF Cafe by purchasing my  ridiculously low−priced products, all of which I created.

RF Cascade Workbook for Excel

RF & Electronics Symbols for Visio

RF & Electronics Symbols for Office

RF & Electronics Stencils for Visio

RF Workbench

T-Shirts, Mugs, Cups, Ball Caps, Mouse Pads

These Are Available for Free

Espresso Engineering Workbook™

Smith Chart™ for Excel

Crane Aerospace Electronics Microwave Solutions: Space Qualified Passive Products

1st-Generation UHF Standards for RFID

RFID is becoming as ubiquitous as printed bar codes. In fact, in many venues, optically scanned bar codes have been entirely replaced with embedded RFID tags. Clothing, high value electronics, packaged software, and even books have been using RFID (sometimes in the form of NFC - near field communications) for many years. Now, major retailers like Wal-Mart have made a commitment to making RFID ubiquitous. In the not-too-distant future, if you want to have your product sold by some of these retailers, you will be required to integrate RFID tags.

The magic price mark for RFID is a couple cents per tag. At that level, RFID can be added to every product and not represent more than a percent or two of the total cost.

This table summaries the protocols used in RID tags that operate in the 800/900 MHz band assigned for ISM (Industrial, Scientific & Medical) use.

  Key Parameters Auto-ID

Class 0

Auto-ID

Class 1

ISO18000-6 A ISO 18000-6 B
Forward

Link

Operating Frequency 902 MHz - 928 MHz 902 MHz - 928 MHz 860 MHz - 930 MHz 860 MHz - 930 MHz
Air Interface AM PWM AM PWM Pulse Interval ASK Manchester ASK
Bit Period NA: 25 µs/12.5 µs

EU: 62.5 µs

NA: 14.25 µs

EU: 66.67 µs

Data ‘0': 20 µs

Data ‘1': 40 µs

125 µs/25 µs
Data Rate NA: 40/80 kbps

EU: 16 kbps

NA: 70.18 kbps

EU: 15.00 kbps

33 kbps (1) 8/40 kbps
Worst-case

Duty Cycle

52%

Data ‘1' low for 6 µs

62.5%

Data ‘1' low for

3To/8

50%

Data ‘0' low for

10 µs

50%

Manchester code

Modulation Depth

[Min, Max]

[20%, 100%] [30%, 100%] [27%, 100%] Nom 15%:

 [13%, 17%

Nom 99%:

 [90%, 100%]

Reverse

Link

Air Interface Passive Backscatter:

FSK

Passive Backscatter:

Pulse Interval AM

Passive Backscatter:

Bi-phase Space AM

Passive Backscatter:

Bi-phase Space AM

Bit Period NA: 25 µs/12.5 µs

EU: 62.5 µs

NA: 7.13 µs

EU: 33.33 µs

25 µs 25 µs
Data Rate NA: 40/80 kbps

EU: 16 kbps

NA: 140.35 kbps

EU: 30.00 kbps

40 kbps (1) 40 kbps (1)
Forward-to-reverse

Link Turnaround

Not Applicable (2) NA: 114 µs

EU: 534 µs

Shall not exceed 100 µs Shall not exceed 100 µs
General Reset Signal Duration 800 µs (CW) 64 µs (CW) 300 µs (CW) 400 µs (CW)
Collision Arbitration Deterministic binary

tree search

Deterministic/Slotted Adaptive Probabilistic binary

tree search (3)

Tag Read Speed Nom: 200 tags/sec

Max: 800 tags/sec

Not specified Nom: 100 tags/sec

(~10 ms/tag)

Nom: 100 tags/sec

(~10 ms/tag)

Tag Capacity Not limited by standard ~300 (4) ~300 (4) ~300 (4)
Memory Memory Type Read-only User programmable User programmable User programmable
Memory Organization EPC: 64/96 bits

Kill Code: 24 bits

Total: >=120 bits

EPC: 64/96 bits

Kill Code: 8 bits

Total: >=104 bits

Up to 256 blocks

w/256 bits/block (64 kBits)

Up to 256 blocks

w/8 bits/block (2 kBits)

Security/

Privacy

Features Moderate

D0/ID1 + 24 bit kill

passcode

None

Reader broadcasts all or part of ID code.

Reader can request kill passcode.

None

Reader broadcasts

UID/SUID. Production set block lock bits. No kill command.

None

Reader broadcasts

UID/SUID. Production set block lock bits. No kill command.

(1) No mention of data rates specific to European operation. Reverse link is always 40 kbps.

(2) For Auto-ID class 0, the tag data response is always known a priori (i.e., nothing has to be computed based on the current bit).

(3) Probabilistic collision arbitration implies that tag selection speed will depend on the tag population size.

      This is a disadvantage.

(4) These standards are limited by the probabilistic nature of their collision arbitration protocols.

      Most of them assume a tag population of ~250 tags.

Source: RF Design, July 2005 , by Rob Glidden and John Schroeter. Click here for the full article.

Crane Aerospace Electronics Microwave Solutions: Space Qualified Passive Products
Werbel Microwave (power dividers, couplers)

Axiom Test Equipment - RF Cafe

Amplifier Solutions Corporation (ASC) - RF Cafe