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High-speed Wireless LAN Technology 
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Ricoh's wireless LAN technology enables high-speed communications in a secure manner
with excellent connectivity.
Improving office IT environment with comfort and security
Wireless LAN becomes popular in offices. Demands are increasing for layout independent
network where PCs, printers, and multi-function printers (MFPs) are connected without cables. An optional board
featuring this technology adds speed and high security to document management including printing and “scan-to-Email” in
a wireless environment. Another advantage of this technology is a stable connection that is not easily affected
by fluctuations in the wireless environment.
Wireless LAN with stability and speed
This technology is carefully implemented to ensure stable, high-speed wireless LAN communications.
The antennas are specifically optimized for desktop and floor-standing printers/MFPs. We integrated features
needed for this new technology into the control LSI (with built-in CPU and memory) with embedded software.
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Figure 1: Option board for desktop devices and installation
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Figure 2: Option board for floor-standing devices and installation
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Ricoh developed the following core modules for the technologies conforming to IEEE802.11a/b/g/i
wireless LAN standards:
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| Figure 3: Modules developed by Ricoh |
(1) Control software corresponding to MAC sublayer
Ricoh developed the control software for the hardware modules in this sublayer and lower-level
layers. The software receives commands from higher-level layers (such as device drivers) and establishes communications
with the destination terminal using protocols conforming to the standards. The development team thoroughly verified
interconnectivity with a variety of terminals, and carefully designed the algorithm to improve connectivity.
(2) Control LSI corresponding to MAC sublayer and PLCP sublayer
The LSI is an SoC (System on Chip) device integrating CPU, memory, and AD/DA converters.
It is a key device that provides data framing, time management, encryption, modulation/demodulation, and interfaces
for MFPs and laser printers. Supported encryption schemes are WEP (ARC4), TKIP (ARC4), and CCMP (AES), and supported
modulation/demodulation schemes are DBPSK, DQPSK, BPSK, QPSK, 16QAM, and 64QAM for primary modulation and DSSS/CCK
and OFDM for secondary modulation. The architecture is optimized for MFPs and laser printers; rich functions
and performance are integrated into one chip.
(3)Radio-frequency (RF) circuit corresponding to PMD sublayer
This circuit supports 14 channels of the 2.4 GHz band and 12 channels of the 5 GHz band.
Support for the 5 GHz band allows users to enjoy high-speed communications in an environment where interference
waves are marginal. The circuit is approved under local regulations in many countries and regions – Japan, USA,
Canada, Europe, China, and Taiwan. While the board is common to all countries and regions, it operates in accordance
with radio wave restrictions of the shipping destinations.
Enabling high speed and high security
The technology supports IEEE802.11a/b/g radio communications standards. It also supports
IEEE802.1X and IEEE802.11i security standards, which stipulate the authentication protocols of the devices, enabling
a level of security comparable to or higher than wired LAN.
Ricoh’s original features and performance in this aspect are as follows:
- High connectivity with a variety of access points (master stations) of different characteristics
- Mostly immune to fluctuations in radio environment (easy connection and support)
- Short time to connect (up to 5 seconds shorter, compared to previous Ricoh models)
- Long communication spans thanks to specially designed antennas (up to 70% improvement over previous Ricoh
models)
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