TM80 Telemetry Monitor Service Manual 3-9 
 
3.2.1 Requirements for Network Feasibility 
Before installing TM80 telemetry monitors, it is very important to confirm network 
feasibility. 
Wireless coverage, WLAN features and AP capability and compatibility are decided 
by infrastructure of network, infrastructure of network can’t be modified easily. If the 
network does not meet the requirements before TM80 is installed, network 
dropping-off may happen easily after installation. 
 
3.2.1.1 Requirements for the Wireless Coverage 
The wireless coverage must be well controlled to ensure that TM80 can achieve the 
maximum data-rate and the lowest packet loss ratio. TM80 data is real-time 
upstream data streams and is similar to VoIP data. Monitoring data carries real-time 
physiologic information about patients. Therefore, reasonable wireless coverage 
must be provided for monitors. In particular, because the telemetry device TM80 is 
worn on human body, the signal may become poorer due to blocking of human 
body. 
 
The requirements of the TM80 for wireless coverage are as follows: 
No.  Item  Requirements of the TM80  Description 
1  Received 
signal 
strengths 
(RSSI) 
≥-65 dBm 
Signal coverage requirement for APs 
connected to the TM80: RSSI value 
displayed on the TM80 
The requirement 
must be met. 
2  Co-channel 
interference* 
≤-20dB 
Measured on the same channel of 
the TM80 
The requirement 
must be met. 
3  Ping  delay  The mean delay of PC or cell phone 
with normal wifi module is smaller 
than 100ms and the packet lost rate 
shall be less than 1%. 
The requirement 
must be met.