OG_MU4-USBIF_v10e 13 Circuit Design, Inc.
OPERATION GUIDE
In systems where a non-directional antenna is required, it is important that the antennas of the transmitting station
and target stations stand vertically in order to exploit communication performance to the maximum. If the planes of
polarization of the radio waves do not match, receive sensitivity may drop significantly.
Note that if, for reasons peculiar to the equipment, the antenna must be inside the case, communication
performance will be very significantly degraded when handled in the ways below, since these methods contravene
antenna theory. It is the responsibility of the user to test performance thoroughly when designing equipment.
1. Putting the antenna inside a metal case
2. Wrapping the antenna around the MU4-USB itself
3. Locating the antenna beside the ground pattern of your circuit board
4. Fitting the antenna inside by bending it
5. Cutting the antenna to make it shorter
The antenna of the MU4-
USB is a 1/4λ whip antenna. Whip antennas are antennas that substitute the ground as
one end of a dipole antenna. For this reason, the ground has a very important meaning. Although the main unit of
the MU2-USB has the function of a ground, in order to exploit its performance fully, connect it to the largest possible
ground pattern when mounting it on your circuit board.
In addition, in the case of two-way communication between fixed stations, inclining the whip antenna of the MU-4
forwards may increase its communication range. Carry out tests in the specific environment of use.
The MU4-USBIF is a test board that uses an USB interface to interface with external equipment. The MU4-USB is
made for test equipment, and is not a stand-alone product. The regulatory compliance assessment of the MU2-USB
in accordance with the RE Directive depends on the final product in which the MU4-USB is embedded. Regulatory
compliance assessment should be carried out on the responsibility of the manufacturer of the final product.
For details of the CE mark, refer to the MU-4 operation guide.
Point:
The MU-4 radio modem has passed the regulatory compliance assessment in accordance with RE Directive as a
stand-alone product, and has received the CE mark.
1. Always use double shield USB cable for connecting the MU4-USB.
2. Devise ways of isolating the MU-4 as far as possible from sources of noise, including noise from other
embedded equipment.
3. Arrange the MU4-USB so that it will not be covere
d by the operator’s hand or the like.
4. The MU4-USB does not have a waterproof structure. If the antenna is located outside the main unit, use a
structure that prevents water droplets from entering the case.
The program that controls the MU4-USB (MU-4 + MU4-USBIF) is a program that accesses the COM port.
The method of developing a program is basically the same as for the MU-4, except for accessing a virtual COM port.
Refer to “Chapter 6 How to Develop a Program” in the MU-4 operation guide.
Chapter 5 How to Develop a Program
4.4 Cautions
4.3 Regulatory Compliance
4.2 The Antenna
