3.3 Transmission Range
The main factors that influence the system transmission range are type and location of the
antennas of the receiver and the transmitter, type of terrain and degree of obstruction of the
link path, sources of interference affecting the receiver, and “Dead” spots caused by signal
reflections from nearby conductive objects. Since the expected transmission range strongly
depends on this system conditions, range tests should categorically be performed before
notification of a particular range that will be attainable by a certain application.
notification of a particular range that will be attainable by a particular application.
The following figures for expected transmission range are considered by using a PTM, a STM or
a TCM radio transmitter device and the RCM or the TCM radio receiver device with preinstalled
whip antenna and may be used as a rough guide only:
•
Line-of-sight connections:
Typically 30m range in corridors, up to 100m in halls
•
Plasterboard walls / dry wood:
Typically 30m range, through max. 5 walls
•
Brick walls / aerated concrete:
Typically 20m range, through max. 3 walls
•
Ferroconcrete walls / ceilings:
Typically 10m range, through max. 1 ceiling
•
Fire-safety walls, elevator shafts, staircases and supply areas should be
considered as screening
.
The angle at which the transmitted signal hits the wall is very important. The effective wall
thickness – and with it the signal attenuation – varies according to this angle. Signals should
be transmitted as directly as possible through the wall. Wall niches should be avoided. Other
factors restricting transmission range:
•
Switch mounted on metal surfaces (up to 30% loss of transmission range)
•
Hollow lightweight walls filled with insulating wool on metal foil
•
False ceilings with panels of metal or carbon fiber
•
Lead glass or glass with metal coating, steel furniture
The distance between EnOcean receivers and other transmitting devices such as computers,
audio and video equipment that also emit high-frequency signals should be at least 0.5m
A summarized application note to determine the transmission range within buildings are
available as download from
www.enocean.com
.
Attention for US applications: Please note that 868 MHz is used in the United States
of America by trunk radio also. A decrease of transmitter range should be
considered, mainly near to radio beacons of fire brigades.
©EnOcean GmbH
Page 16 of 20
RCM 152 User Manual V1.31
