scope:

This European Telecommunication Standard (ETS) specifies the minimum performance parameters for terrestrial fixed services radio communications equipment, as given below, for operation in the 13 GHz, 15 GHz and 18 GHz frequency bands (i.e. 12,75 to 13,25 GHz, 14,50 to 15,35 GHz and 17,70 to 19,70 GHz).

The equipments covered by this ETS are intended for operation with about 28 MHz basic channel spacing with frequency re-use either in 14 MHz interleaved mode or in co-channel mode (definitions are in ITU-R Recommendation F.746 [27]).

This ETS covers equipment for the transmission of sub-Synchronous Transport Module level-1 (STM-1) digital signals with a Virtual Container-3 (VC-3) payload capacity. The standardization of sub-STM-1 radio systems for 13 GHz, 15 GHz and 18 GHz bands has been prepared to ensure the compatibility with the existing plesiochronous and the new synchronous systems concerning frequency plans and performance. The architecture and functional aspects should be in accordance with ITU-R Recommendation F.750 [7] and transmission characteristics and performance requirements in accordance with ITU-R Recommendation F.751 [8].

This ETS do not cover aspects related to test procedures and test conditions which are currently under study in TM4.

The application of these Digital Radio Relay Systems (DRRS) is anticipated to be for point-to-point links in local, regional and national networks, mobile base station connections and customer access links. Consideration has to be given to special requirements of the local network (e.g. simple towers with less space for antenna, different network structures with high density nodes).

The systems considered in this ETS are intended to operate on average hop lengths about 15 km for 18 GHz band, 20 km for 15 GHz band and 30 km for 13 GHz band.

Equipment should be designed in order to meet network performance and availability requirements defined by ITU-T Recommendations G.821 [18] and G.826 [19], following the criteria defined in ITU-R Recommendations F.634 [3], F.695 [32], F.696 [5], F.697 [6], F.1092 [30] and F 1189 [31], for high or medium or local grade or the international or the national portion of the digital connection.

The parameters to be specified fall into two categories:

a) those that are required to provide compatibility between Radio Frequency (RF) channels occupied by different sources of equipment on the same route connected either:

- to separate antennas; or

- to separate polarization of the same antenna;

b) parameters defining the transmission quality of the proposed system.

The standardization deals with Intermediate Frequency (IF), RF and baseband characteristics relevant to sub-STM-1 Synchronous Digital Hierarchy (SDH) transmission. Spurious emissions and ElectroMagnetic Compatibility (EMC) requirements are also included in this ETS.

Safety aspects are outside the mandate of ETSI and they will not be considered in this ETS.