Product Features
Operating at Spread Spectrum Band
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The setting can be done through the built-in Command Line interface (CLI), or through the configuration
and maintenance application software running either on PC – AWLaunch.
The diagnostic feature of the FH915 system provides the information to monitor and maintain user’s
communications link. The output transmit power, receive signal strength (RSSI), antenna/feedline
condition, and data decode performance are transmitted online without application interruption.
The product is designed for maximum performance and reliability even in the harshest environments.
Plug and play at its best, robust, withstanding the most adverse of conditions.
2.2. Operating at Spread Spectrum Band
The Spread Spectrum (SSR) technique in which a signal is transmitted on a bandwidth considerably
larger than the frequency content of the original information.
Spread-spectrum telecommunications is a signal structuring technique that employs direct sequence,
frequency hopping or a hybrid of these, which can be used for multiple access and/or multiple functions.
This technique decreases the potential interference to other receivers while achieving privacy. Spread
spectrum generally makes use of a sequential noise-like signal structure to spread the normally
narrowband information signal over a relatively wideband (radio) band of frequencies. The receiver
correlates the received signals to retrieve the original information signal.
2.3. Modulation Technique
FH915 radio transceiver uses two bands: 902-928 MHz ISM license free USA band and European CEPT
license free 868-870 MHz band. In 902-928 MHz band FH915 radio uses frequency hopping
transmission techniques.
The design is based on high-level modulation techniques which include:
The following are its key benefits:
• Ten optimized Frequency Hopping Patterns provides simultaneous operating of several units with
minimum of mutual interference.
• FEC coding scheme used with GMSK and 4FSK modulations is based on Convolutional code
• and the Viterbi decoding algorithm which is the most resource-consuming, but it does Maximum
likelihood decoding.
Modulation/ Channel Spacing
902.0-928.0
GMSK – Minimal Shift Keying with Gaussian Filtering 64.0 kbps, 128 *200.0 kHz
4FSK- Four Level Frequency Shift Keying (planned)
128.0 kbps, 128 *200.0 kHz
