ISL37400M-EVAL Datasheet, PDF (2/6 Pages) Intersil Corporation – PRISM 2.5 11Mbps Wireless Local Area Network miniPCI

ISL37400M-EVAL
TABLE 1. TYPICAL OPERATING RANGE (Notes 2, 4)
DATA RATE (Mbps) INDOOR RANGE OUTDOOR RANGE
11
120 feet (37 meters) 500 feet (152 meters)
5.5
200 feet (61 meters) 800 feet (243 meters)
2
240 feet (73 meters) 1300 feet (396 meters)
1
300 feet (91 meters) 1750 feet (533 meters)
NOTES:
1. Throughout this document, all references to ‘miniPCI’, ‘WLAN
adapter’, ‘adapter’, or ‘card’ refer to a card assembly conforming
to the mechanical size specifications of the miniPCI Type 3A.
2. The range will vary in different operating environments due to
effects such as building construction.
3. At present, PTTU supports Windows 95, 98, NT, 2000 and ME
4. Data taken using custom proprietary antennas in a custom
proprietary laptop computer.
Functional Overview
The WLAN miniPCI is designed to operate in the 2.4GHz ISM
frequency band, channels 1 to 11, as specified by the FCC in
the USA. The card will also operate on channels 12 through 14,
where permitted by local regulatory authorities. Radio
equipment must be certified in a country prior to use. Refer to
Table 4 for a list of countries and agencies that have approved
the ISL37400M-EVAL for operation.
The Intersil PRISM Chip Set allows for high level integration
for reduced size, increased throughput, improved radio
performance and faster time to market. The WLAN miniPCI
implements DSSS technology providing superior noise and
signal jamming immunity, including less severe impact from
unintentional radiators such as microwave ovens. The user
can connect the miniPCI in an ad-hoc peer-to-peer
networking scheme, allowing for instant network setup in any
office environment. By using an access point, the wireless
LAN can be set up to allow for a greater number of users to
interconnect, and to increase the coverage area. With a portal
(i.e., Access Point), the wireless LAN can be easily
connected into an existing wired LAN, allowing for easy
expansion of the service.
Compared to the PRISM II chip set, the PRISM 2.5
generation offers:
• Low-loss front end designed for maximum range
• Higher level of chip integration and less peripheral
components, reducing material costs
• Support of optional IEEE802.11 Short Preamble for
significantly increased data throughput with room for
additional user-defined functions
• Has a miniPCI interface/Type 3A form factor
A complete reference design for the ISL37400M is available to
ensure minimum time-to-market. This information contains
details for manufacturing a miniPCI WLAN assembly,
including Gerber PC board files, an accurate bill of material
with component sourcing and complete mechanical drawings
and a complete radio description and test plan.
Related Literature
• Tech Brief TB337, Intersil Corporation, A Brief Tutorial on
Spread Spectrum and Packet Radio [1].
• Tech Brief TB382, Intersil Corporation, Measurement of
WLAN Receiver Sensitivity [2].
• Application Note AN9850, Intersil Corporation,
Complementary Code Keying Made Simple [3].
• Application Note AN9829, Intersil Corporation, Brief
Tutorial on IEEE802.11 Wireless LANs [4].
• Application Note AN9820, Intersil Corporation, A
Condensed Review of Spread Spectrum Techniques for
ISM Band Systems [5].
The ISL3874 Media Access Controller
(MAC) Protocol Handler
The ISL3874 MAC/Baseband Processor and its firmware are
responsible for running the IEEE802.11 protocol in the
WLAN card. This section describes the features of
IEEE802.11 that are implemented.
The functions supported by the STA (station) Firmware are:
• CSMA/CA (Carrier Sense Multiple Access with Collision
Avoidance) with random backoff
• WEP security
• Short/long preamble with multirate
• RTS/CTS handshake (ready to send/clear to send) and
NAV management (network allocation vector)
• MAC level acknowledgments
• Retransmission of unacknowledged frames
• Duplicate detection and rejection
• Broadcast and multicast frames
• Fragmentation and re-assembly
• Power management (planned)
• Timestamp synchronization
• DCF (distributed coordination function)
• PCF (point coordination function)
• Beacon generation in an ad-hoc network
• Probe response generation in an ad-hoc network
Card Information Structure
The standard Intersil WLAN miniPCI will be supplied with
information embedded in the Plug and Play (PnP) shown in
Table 2. It should be noted that in most systems this
information is displayed when the card is inserted.
Customization of the PnP for specific customer requirements
is available upon request, to enable customer information to
be displayed when the card is inserted.
2