2. Products
  3. Radio modem
  4. MU-2-R
  5. Features and functions

Wireless module product information, such as a wireless modem - CIRCUIT DESIGN,INC.

Features and functions

MU-2-R internal block

MU-2-R internal block

Serial data transmission with simple, dedicated commands

The MU-2-R uses Circuit Design’s unique simple, dedicated commands. Setting channels and all other controls can all be performed with commands.

Example 1: Sending the 5 characters “ABCDE”
Example 2: Changing the channel to 08

Relay function (maximum 10 stations)

You can make a relay with a maximum of 10 stations using the route command.

Example of transmitting data (ABCDE) to the target station with Equipment ID EI=04 via relay station 1 (EI=02) and relay station 2 (EI=03).

Reed Solomon Coding

One of several FEC block codes, it has strong error correction ability and the characteristic of correcting data errors caused by burst noise. Reed-Solomon codes are used in compact disks, satellite communications, and digital TV broadcasting


The MU-2 uses Reed-Solomon code for FEC, which reduces errors occurring due to burst noise and/or noise at low received signal level, and it improves the receive sensitivity of the equipment by more than 5 dB *1.

Error correction protocol data format   *2


MU-2-R data block

MU-2-R data component: 1 to 255 bytes variable


User data


Reed-Solomon code specification

Code: RS (255, 247)


1 - 32 bytes

8 bytes

Primitive polynomial: X8 + X4 + X3 + X2 + 1


33 - 64 bytes

8 bytes

Interleave: None




Error correction rate: 10% error or more


224 - 225 bytes

8 bytes

  • *1 In interleave mode / Measured at Circuit Design, Inc.
  • *2 There are operation modes with or without error correction. Select the appropriate mode depending on the situation at the site and the application

How, When does FEC help RF communication

VS Error in burst noise (Measurement conditions: 4,800 bps / Data size 4 bytes)
Error correction reduces influence from noise with is generated suddenly or is continuously generated at a dead point during mobile use with multi path.
VS Error in random noise (Measurement conditions: 4800 bps / Data size 32 bytes / Received signal level -114 dBm)
Error correction reduces influence from random noise which appears at a low received signal level
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