20-101-1221 Rabbit Semiconductor, 20-101-1221 Datasheet - Page 44

• Manufacturer Part Number: 20-101-1221
• Description: RCM4400W (JAPAN TELEC CERTIFIED)
• Manufacturer: Rabbit Semiconductor
• Series: RabbitCore®r

Specifications of 20-101-1221

• Frequency: 2.4GHz
• Modulation Or Protocol: 802.11 b
• Power - Output: 16dBm
• Voltage - Supply: 3.3V
• Current - Receiving: 450mA
• Current - Transmitting: 450mA
• Data Interface: Connector, 2 x 25 Header
• Memory Size: 512K Flash, 1MB SRAM
• Antenna Connector: SMA
• Operating Temperature: -20°C ~ 85°C
• Package / Case: Module
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Applications: -
• Sensitivity: -
• Data Rate - Maximum: -
• Other names: 316-1147

4.2.2 Wi-Fi
Figure 9 shows a functional block diagram for the Wi-Fi circuits.
Figure 9. RCM4400W Wi-Fi Block Diagram
The Wi-Fi transmission is controlled by the onboard FPGA chip at U14. The primary
functions of this FPGA are to implement the 802.11b baseband Media Access Control
(MAC) functionality, and to control the 802.11b integrated UBEC UW2453 transceiver.
The serial flash programs the FPGA automatically whenever power is applied. Once con-
figured, the FPGA performs all of the 802.11b data encoding and decoding, radio configu-
ration, and radio control functions.
The data interface between the FPGA and the UBEC UW2453 based 802.11b radio section
consists of a D/A converter and an A/D converter. Both devices convert “I” and “Q” data
samples at a rate of 40 MHz.
The UBEC UW2453 is a single-chip transceiver with integrated power amplifier for the
2.4 GHz Industrial, Scientific, and Medical (ISM) band. It is configured and controlled by
the FPGA via a 3-wire serial data bus. The UW2453 contains the entire receiver, transmit-
ter, VCO, PLL, and power amplifier necessary to implement an 802.11b radio.
The UW2453 can transmit and receive data at up to 11MBits/s in the 802.11b mode. It
supports 802.11b channels 1–13 (2.401 GHz to 2.472 GHz). The data modulate the chan-
nel carrier in such a way so as to produce a spread spectrum signal within the 22 MHz
channel bandwidth of the selected channel. The channel numbers and associated frequen-
cies are listed below in Table 4.
The Wi-Fi channels have a certain amount of overlap with each other. The further apart
two channel numbers are, the less the likelihood of interference. If you encounter interfer-
ence with a neighboring WLAN, change to a different channel. For example, use channels
1, 6, and 11 to minimize any overlap.
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RabbitCore RCM4400W