jrc current assignment criteria using ofw49
TRANSCRIPT
Joint Radio Company:
Making the spectrum and
technology work for your business
www.JRC.co.uk
Alessandra LeesJoint Radio Company Ltd
[email protected]: 02077065196Skype: alexlees_jrc
JRC current assignment criteria using OfW49
ST(17)006ST(17)006
Joint Radio Company:
Making the spectrum and
technology work for your business
www.JRC.co.uk
JRC assignments key points
• Generally follow ACP including non-adjacent cell channels for additional capacity.
• No longer assign inter-leave channels – not compatible with digital equipment. Some existing systems still use them.
• Cross polar discrimination also used.
• Standard outstations are those with 12element Yagi
• Non-standard outstations not used in calculations of systems EIRP or interference.
Joint Radio Company:
Making the spectrum and
technology work for your business
www.JRC.co.uk
Basic 12 cell
repeat pattern
Worst case
150km cell
centre to cell
centre.
Worst case
200km
interference
check
Figure 1 taken from OfW49 document: https://www.ofcom.org.uk/__data/assets/pdf_file/0026/77336/tfac_ofw49.pdf
Joint Radio Company:
Making the spectrum and
technology work for your business
www.JRC.co.uk
Figure 2 taken from OfW49 document: https://www.ofcom.org.uk/__data/assets/pdf_file/0026/77336/tfac_ofw49.pdf
Maximum path loss assigned = 143dB
Total path loss = free space loss + terrain obstruction loss+ clutter loss
Clutter loss limited to 20dB, up to 30dB considered on case by case basis.
Joint Radio Company:
Making the spectrum and
technology work for your business
www.JRC.co.uk
Figure 6 taken from OfW49 document: https://www.ofcom.org.uk/__data/assets/pdf_file/0026/77336/tfac_ofw49.pdf
Maximum end to end circuit loss assigned = 134dB
EECL= total path loss + (total scanner losses – scanner gain) + (total
outstation losses – outstation gain)
Total scanner/outstation losses include:
Feeders
Other losses:
Other miscellaneous loss
Connector loss
Feeder tail loss
Antenna tail loss
Joint Radio Company:
Making the spectrum and
technology work for your business
www.JRC.co.uk
Assigning path: End to End Circuit Loss (EECL)
Information taken from JRC authorisation document
Minimum EIRP
limited to -20dBW
Exceeds EECLmax
Joint Radio Company:
Making the spectrum and
technology work for your business
www.JRC.co.uk
EIRP
Receiver input port level = -122dBW (-117dBW duplicated equipment with
common antenna)
Calculate EIRP:
Scanner EIRP = Outstation receiver input port level + Loss to Outstation• Loss to Outstation = EECL - Sc Feeder Loss – Sc other loss + Sc gain
• If the worst outstation EECL is > EECLmax then use EECLmax
Outstation EIRP = Scanner receiver input port level + Loss to Scanner• Loss to Scanner = EECL – Os Feeder Loss – Os other loss + Os gain
• If the worst outstation EECL is > EECLmax then use EECLmax
Joint Radio Company:
Making the spectrum and
technology work for your business
www.JRC.co.uk
2011Loss to Outstation =
EECLmax - Sc Feeder Loss – Sc other loss + Sc gain
123.9dB - 3dB – 1dB + 8.1dB = 128dB
Scanner EIRP =
Receiver input port level + Loss to Outstation
= -122.0dBW + 128dB = 6dBW
Joint Radio Company:
Making the spectrum and
technology work for your business
www.JRC.co.uk
2011
Maximum transmitter output powers for the assigning path:(unprotected or protected two aerial working)
Scanner:
Tx power (dBm) = outstation wanted signal (-92 dBm) + EECLmax
(-30 for dBW)
Outstation:
Tx power (dBm) = scanner wanted signal + Individual EECL (or EECLmax)
A protected single common aerial system has an extra 5dB receive signal
level (-87dBm)
Joint Radio Company:
Making the spectrum and
technology work for your business
www.JRC.co.uk
Figure 3 taken from OfW49 document: https://www.ofcom.org.uk/__data/assets/pdf_file/0026/77336/tfac_ofw49.pdf
Extra 5dB
passive splitter
for receive path
Joint Radio Company:
Making the spectrum and
technology work for your business
www.JRC.co.uk
Summary of current OfW 49
Assignment Criteria Current OfW 49
Unfaded wanted signal -92dBm
Interference + Noise 99.9% ≤ -114 dBm
Unfaded W/U 22dB
Maximum path loss 143dB
Maximum EECL 134dB