Wireless Technology; Wireless Technology Overview; Intended Wireless (Electromagnetic) Environment - Invacare LINX ACU User Manual

9 Wireless Technology

9.1 Wireless Technology Overview

The LiNX control system makes use of Bluetooth wireless
technology. Bluetooth is a wireless communications system
that is designed to operate in short-range wireless personal
area networks (WPAN).
LiNX supports both the Smart (low energy) and Classic
Bluetooth protocols. These operate in the spectrum range
2.400 GHz to 2.4835 GHz industrial, scientific and medical
(ISM) band. Bluetooth Classic uses 79 x 1MHz channels
and Bluetooth Smart uses 40 x 2MHz channels. Within a
channel, data is transmitted using Gaussian frequency shift
modulation. The bit rate is 1Mbit/s, and the maximum
transmit power is 5mW. Both Bluetooth protocols use
frequency hopping to counteract narrowband interference
problems.
Bluetooth Technology Specifications
Technical Classic Bluetooth
Specification
Class
Distance/Range
(theoretical max.)
Over the Air Data
1–3 Mbit/s
Rate
Application
0.7–2.1 Mbit/s
Throughput
1195718-A
Smart (low
energy)
Bluetooth
Class 2
10m (33ft)
1 Mbit/s
0.27 Mbit/s
Technical Classic Bluetooth
Specification
Security
56/128-bit and
application layer
user defined
Robustness Adaptive fast
frequency
hopping, FEC,
Latency (from a Typically 100 ms
non-connected
state)
Network Topology
Power
Consumption
Service Discovery
Profile Concept
9.2 Intended Wireless (Electromagnetic)
Environment
The intended environments for the LiNX wheelchair are
defined as the users home, assisted living facilities, nursing
Wireless Technology
Smart (low
energy)
Bluetooth
128-bit AES with
Counter Mode
CBCMAC and
application layer
user defined
Adaptive fre-
quency hopping,
Lazy Acknowl-
fast ACK edgement, 24-bit
CRC, 32-bit Mes-
sage Integrity
Check
6 ms
Scatternet
5 mW
Yes
Yes
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