OG_MU-4-434_v10e Circuit Design, Inc.
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OPERATION GUIDE
4.9 Antenna Power Setting
The MU-4 is equipped with an antenna power switching function which can lower the antenna power (output
power) from 10 mW to 1 mW. When communicating in a small area, setting the unit to 1 mW makes it possible to
share radio wave resources effectively with many systems. To lower the power, issue the ‘@PW’ command.
4.10 Communication Protocols
The MU-4 has a standard protocol and error correction protocols.
Of the error correction protocols, the interleave method has stronger error correction ability.
1. Standard protocol: A protocol normally used when error correction is not performed.
2. Error correction protocol: Communication with error correction using Reed-Solomon code.
3. For error correction protocols, there are three types of protocol - ‘without interleave’ ‘with interleave 1’ and ‘with
interleave 2’.
* To set the communication protocol to the error correction protocol (error correction on), set to ‘ON’, ’I1’ or ’I2’
using the ‘@EC’ command with the ‘/W’ command option.
* The standard protocol is a protocol used when the error correction protocol is off.
The error correction protocol
An error correction function with Reed-Solomon codes which corrects errors on the receiver side.
Reed-Solomon codes are effective in an environment where bust errors occur and reliable communication is
required. In conventional communication systems, if an error occurs in the data sent between radios, the sent
packet is discarded and a new packet must be sent, but by using error correction protocols for communication, the
number of retries can be considerably reduced. However note that the communication speed with error correction
is lower due to internal processing. Use the standard protocol if communication speed is important.
Effective radio communication speed (actual measurement value when transmitting 8,352 bytes)
1. Standard protocol: 3,400 bps
2. Error correction protocol (without interleave): 2,300 bps
*Basically communication is only possible between the same protocols.
Note
