I am fully supportive of opensource initiatives and welcome this position by DASH7. However I am concerned by the use of the 433 MHz Spectrum (433.92 MHz) which appears in ISO/IEC 18000-7. The world governing body for radio allocation is the ITU and the position is as below:
In ITU region 2 (the Americas), the frequencies that LPD433 uses are within a band allocated to amateur radio. In the United States LPD433 radios can only be used under FCC amateur regulations by properly licenced amateur radio operators. The conflicting allocations have been something of a nuisance to US amateur operators due to use of the equipment by European tourists in the U.S
So in the USA you are going to need at least a Technician class amateur license to operate in the 70 cm band where 433 MHz lives. 433 MHz is primarily for government radiolocation and secondary for amateur radio within the US.
Title 47: Telecommunication - PART 97—AMATEUR RADIO SERVICE
Subpart D—Technical Standards
§ 97.301 Authorized frequency bands.
"(a) For a station having a control operator who has been granted a Technician, Technician Plus, General, Advanced, or Amateur Extra Class operator license, who holds a CEPT radio amateur license, or who holds any class of IARP:"
UHF - 70 cm
ITU Region 2 420–450 MHz
Sharing Requirements (a), (b), (f)
http://www.ecfr.gov/cgi-bin/text-idx?c= ... .4&idno=47
http://www.ntia.doc.gov/files/ntia/publ ... lochrt.pdf
Page 27 in pdf
http://transition.fcc.gov/oet/spectrum/ ... ctable.pdf
Within the UK the primary user of the 430MHz to 440MHz is the military for their communications network. The secondary users are Radio Amateurs who have to accept interference from the primary user but may not cause interference to the primary user. Both these users have the capability to transmit RF power in the region of 150W to 400W within this band.
This level of RF field strength will easily deafen and render inoperative any low power receiver lacking sufficient filtering and cross modulation capacity which will result in the analogue front end RF receiver being desensitised and unable to hear its intended signal. The affected area could be of a radius from 2 to 5 miles depending on terrain and capabilities for adjacent channel rejection of the receiver .
I do hope due consideration is given to alternative frequency bands.
It is easy enough to tow away a car till it is sufficiently far enough away from a military or amateur transmitter so that it can receive a signal from its key fob etc. Not so easy if you have this problem in a fixed building especially where the transmissions are of an intermittent nature. This is probably why ZigBee and Z-Wave have avoided this band. This inband signal blocking harms the public perception of the reliability of radio control and monitoring links and so does need to be avoided.
This is a great idea but needs implementation in a more suitable frequency band.