Wireless Technology; Wireless Technology Overview; Intended Wireless (Electromagnetic) Environment; Linx Wireless Functions - Invacare LINX REM400 User Manual

10 Wireless Technology

10.1 Wireless Technology Overview

The LiNX control system uses 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 1 MHz channels, and Bluetooth Smart uses 40 x
2 MHz 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.
Technical Specification
Class
Distance/Range
(theoretical maximum)
Over the Air Data Rate
Application Throughput
Security
Robustness
Latency (from a non-
connected state)
Network Topology
Power Consumption
Service Discovery
Profile Concept

10.2 Intended Wireless (Electromagnetic) Environment

The intended environments for the LiNX wheelchair are defined as the user's home, assisted living facilities, nursing homes,
vocational settings and healthcare facilities. Across these environments, numerous medical and non-medical equipment items also
operate wirelessly.

10.3 LiNX Wireless Functions

The LiNX control system functions that use Bluetooth include:
Mouse mover—controls the mouse cursor on a PC, laptop or other portable device.
l
Remote diagnostics—provides status information of the powered wheelchair (battery status, fault conditions etc.).
l
Configuration—allows a trained provider, dealer, therapist or clinician using the programming and diagnostic tools to configure
l
the LiNX control system.

10.3.1 Mouse Mover

The system can operate as a standard wireless PC mouse, where the joystick or other user input can be used to move the cursor on
the screen on a PC, laptop or other similar device. Buttons within the system can also be used to emulate a "left click" and "right
click".
When in Mouse Mover mode, the wheelchair is stationary and unable to drive.
60126081-C
Bluetooth Technology Specifications
Classic Bluetooth
Class 2
10 m (33 ft)
1-3 Mbit/s
0.7-2.1 Mbit/s
56/128-bit and application layer
user defined
Adaptive fast frequency
hopping, FEC, fast ACK
Typically 100 ms
Scatternet
5 mW
Yes
Yes
Smart (Low Energy) Bluetooth
1 Mbit/s
0.27 Mbit/s
128-bit AES with Counter Mode CBCMAC and application layer
user defined
Adaptive frequency hopping, Lazy Acknowledgment, 24-bit CRC,
32-bit Message Integrity Check
6 ms
10 Wireless Technology
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