scope:

The present document specifies technical characteristics and methods of measurements for C-band meteorological radar systems intended for the surveillance and classification of hydrometeors with the following characteristics:

• Operating in the following frequency range:

- 5 250 MHz to 5 850 MHz

• Utilizing unmodulated pulses or phase/frequency modulated pulses also known as pulse compression.

• The maximum output power (PEP) does not exceed 1 MW (i.e. 90 dBm).

• The transceiver antenna connection and its feeding RF line are using a hollow metallic rectangular or elliptic waveguide.

• The antenna is rotating and can be changed in elevation.

• The antenna feed is waveguide based and the antenna is passive.

• The orientation of the transmitted field from the antenna can be vertical or horizontal orientated or it can be both simultaneously.

• At the transceiver output a RF circulator is used.

NOTE 1: Since transceiver and antenna are based on hollow metallic rectangular waveguide the frequency range for measurements that needs to be addressed covers 3 152 MHz to 26 GHz. The lower limit of this frequency range is obtained as the cut-off frequency of the generally used WR187/WG12 waveguide according to IEC 60153-2 [i.2]. The upper limit corresponds to the upper limit stated in ERC/Recommendation 74-01 [1], Table 1.

NOTE 2: Since at the transceiver output a RF circulator is used, it is assumed that the transceiver characteristics remain independent from the antenna.

NOTE 3: Meteorological radar systems covered by the present document are expected to use the band 5 250 MHz to 5 850 MHz. According to provision 5.452 of the ITU Radio Regulations [4], ground-based radars used for meteorological purposes in the band 5 600 MHz to 5 650 MHz are authorized to operate on a basis of equality with stations of the maritime radionavigation service.

NOTE 4: Further technical and operational characteristics of meteorological radar systems can be found in Recommendation ITU-R M.1849-1 [i.3].

NOTE 5: The relationship between the present document and essential requirements of article 3.2 of Directive 2014/53/EU [i.1] is given in Annex A.