Technical data

Technical Datasheet
&
User’s Manual
Narrowband multi-channel data radio modem
LinkWiser™-S400M Rev. 2.1
Cellution Inc.
#317, NKIC, 48-84 Honguen-1dong, Seodaemun-gu, Seoul, Korea Zip: 120-760
Enquiries: [e-mail]
/ [e-mail]
Voice: [phone] / Fax: [phone]
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11. INTEGRATION GUIDE
LinkWiser™-S400M Rev. 2.1 owns a voltage regulator which always supplies 2.8VDC to the entire
circuit except POWER APLIFIER that receives 6.5VDC ~ 24VDC of input voltage directly. And this is
for stable operation & performance especially in RF front end side. Nevertheless, qualified external
power supply is necessary, which must be in 6.5VDC ~ 24VDC with more than 40dB of ripple rejection
by an external voltage regulator.
11-1. COMMUNICATION RANGE
The communication range is a key factor to be considered. And there are some considerable variants
to get preferred communication distances.
9 Type and location of antennas in use
9 Type of terrain and degree of obstruction of the link path
9 Sources of interference affecting the receiver
9 "Dead" spots caused by signal reflections from nearby conductive objects
9 Data rate and degree of filtering employed
However, our agency approved antennas must be applied to inherit our modular approval.
11-2. ANTENNA MATCHING
Most important for effective data transmission is selection of a good antenna, and RF grounding, both
for the transmitter and the receiver. Without a good antenna it is impossible to transmit data over a
long distance.
The LinkWiser™-S400M Rev. 2.1 has the SMA connector basically. And, it doesn’t require additional
antenna matching if you purchase Cellution’s antennas.
In most cases the following basic rules will help you.
9 Connect an antenna with 50-Ohm impedance.
9 Place the antenna vertically, straight up or down from the transmitter and receiver module.
9 Do not cover the antenna with metal parts.
The connection of the metal surface of the receiver case to a larger metal part (ground plane) will
increase radiation efficiency. Such metal parts should not be placed near the antenna.
The human body can have a similar effect to metal objects. Pocket receivers should be held in the
hand and held in a position away from the body.
Best range is achieved if the transmitter and receiver antenna are in direct line of sight. Any object in
between the transmitter and receiver antenna, and metallic objects in particular, will decrease the
range.
The transmission is influenced by reflections of the transmitter signal on metallic surfaces and building.
There is possibility that data errors will occur due to overlapping of the direct and reflected signals.
11-3. MODULE MODIFICATION
The module must not be physically altered in any way.
11-4. END PRODUCT LABELING REQUIREMENTS
Pursuant to KCC (South Korea) or ARIB (Japan) regulations, the end product must be type approved.
The LinkWiser-S400M, a complete modem (+6.5VDC to +36VDC) that is type approved by South
Korean KCC.