Radar on 2.4GHz with standard WiFi-Components - Regulations - Page 1
Forum section: electronics / rf-microwave

author: SaabFAN
author_rank: Frequent Contributor
timestamp: February 09, 2018, 07:24:01 pm
content: Hi,I'm interested in building and experimenting with a CW-Radar built from typical wifi-components found in everyday devices, like WLAN-Cards for Laptops, of which I have a bunch lying around.Of particular interest for me is the application as a navigation-radar at sea (the river Elbe and the Baltic Sea to be precise) with a transmit-power of about 5W (the E-Class for HAM-Radio operators in Germany permits 5W PEP) and using "Cantennas" or patch-antennas as transmit and receive-antennas.Unfortunately, I haven't found anything about the regulations regarding operating a CW-transmitter with a bandwidth of about 500 kHz to 1 MHz. Would is be permitted to operate such a device in the 13cm band? And if so, are there portions of the band that cannot be used? I figure that the area allocated to amateur satellites would suffer the least impact, as satellites are up in the sky and this radar-device would scan the horizon at a height of about 4 meters, which means the signal would be rejected by antennas directed at satellites.If that isn't the case, please educate meDisclaimer: I haven't applied for a HAM-Radio license yet, but would do so before starting to operate any transmitters of course.Thx

author: Lord of nothing
author_rank: Super Contributor
timestamp: February 10, 2018, 10:30:32 am
content: Keep in Mind also in Germany you have to Pay for the Call Sign a Monthly fee also the exam Cost some Money.

author: Neganur
author_rank: Unknown
timestamp: February 11, 2018, 09:08:20 am
content: https://www.bundesnetzagentur.de/SharedDocs/Downloads/DE/Sachgebiete/Telekommunikation/Unternehmen_Institutionen/Frequenzen/Frequenzplan.pdf?__blob=publicationFile&v=9Which one of these entries are you referring to with 5W ERP?

author: SaabFAN
author_rank: Frequent Contributor
timestamp: February 11, 2018, 01:29:26 pm
content: This one:https://www.bundesnetzagentur.de/SharedDocs/Downloads/DE/Sachgebiete/Telekommunikation/Unternehmen_Institutionen/Frequenzen/Amateurfunk/AmtsblattverfuegungenAFu/Mitt_695_Amateurfunkdienst_Nutzung_der_Frequenzbereiche_2320–2450_MHz_und_5650–5850_MHz_durch_Klasse_E.pdf?__blob=publicationFile&v=3HAM-Radio frequencies and maximum power are regulated in a separate publication than the "normal" Frequenzplan.

author: Neganur
author_rank: Unknown
timestamp: February 11, 2018, 03:20:03 pm
content: ah that solves the mysteryLook at Anlage 1 "Nutzungsbestimmungen 9 und 13" (starting at page 9) ofhttps://www.gesetze-im-internet.de/afuv_2005/AFuV.pdf9: "Die maximal zulässige belegte Bandbreite einer Aussendung beträgt 10 MHz und bei Fernsehaussendungen 20 MHz."So, you may use a bandwidth of 10 MHz.13: "[...] In den Frequenzbereichen 435 - 438 MHz, 1.260 - 1.270 MHz, 2.400 - 2.450 MHz und 5.650 - 5.670 MHz sind andere sekundäre Funkdienste gegenüber dem Amateurfunkdienst über Satelliten bevorrechtigt. [...]"This says that in 2.4...2.45 GHz those ham that do satellite stuff must endure disturbance from other secondary use services (so they are not a protected primary use service)I don't know if your intended RADAR use is limited otherwise (radio services are usually divided into what they are used for, i.e. telemetry or communication etc). Plus there may be primary services that you must not interfere with (military maritime and mobile communication?).