1、 Recommendation ITU-R M.1730-1(10/2009)Characteristics of and protection criteria for the radiolocation service in the frequency band 15.4-17.3 GHzM SeriesMobile, radiodetermination, amateur and related satellite servicesii Rec. ITU-R M.1730-1 Foreword The role of the Radiocommunication Sector is to
2、 ensure the rational, equitable, efficient and economical use of the radio-frequency spectrum by all radiocommunication services, including satellite services, and carry out studies without limit of frequency range on the basis of which Recommendations are adopted. The regulatory and policy function
3、s of the Radiocommunication Sector are performed by World and Regional Radiocommunication Conferences and Radiocommunication Assemblies supported by Study Groups. Policy on Intellectual Property Right (IPR) ITU-R policy on IPR is described in the Common Patent Policy for ITU-T/ITU-R/ISO/IEC referenc
4、ed in Annex 1 of Resolution ITU-R 1. Forms to be used for the submission of patent statements and licensing declarations by patent holders are available from http:/www.itu.int/ITU-R/go/patents/en where the Guidelines for Implementation of the Common Patent Policy for ITU-T/ITU-R/ISO/IEC and the ITU-
5、R patent information database can also be found. Series of ITU-R Recommendations (Also available online at http:/www.itu.int/publ/R-REC/en) Series Title BO Satellite delivery BR Recording for production, archival and play-out; film for television BS Broadcasting service (sound) BT Broadcasting servi
6、ce (television) F Fixed service M Mobile, radiodetermination, amateur and related satellite services P Radiowave propagation RA Radio astronomy RS Remote sensing systems S Fixed-satellite service SA Space applications and meteorology SF Frequency sharing and coordination between fixed-satellite and
7、fixed service systems SM Spectrum management SNG Satellite news gathering TF Time signals and frequency standards emissions V Vocabulary and related subjects Note: This ITU-R Recommendation was approved in English under the procedure detailed in Resolution ITU-R 1. Electronic Publication Geneva, 200
8、9 ITU 2009 All rights reserved. No part of this publication may be reproduced, by any means whatsoever, without written permission of ITU. Rec. ITU-R M.1730-1 1 RECOMMENDATION ITU-R M.1730-1 Characteristics of and protection criteria for the radiolocation service in the frequency band 15.4 -17.3 GHz
9、 (Question ITU-R 226/5) (2005-2009) Scope This Recommendation provides the technical characteristics and protection criteria for the radiolocation systems operating and planned to operate in the band 15.4-17.3 GHz. It was developed as a resource document intended to support sharing studies in conjun
10、ction with Recommendation ITU-R M.1461 addressing analysis procedures for determining compatibility between radars operating in the radiolocation service and other services. The ITU Radiocommunication Assembly, considering a) that antenna, signal propagation, target detection and large necessary ban
11、dwidth characteristics of radar to achieve their functions are optimum in certain frequency bands; b) that the technical characteristics of radars operating in the radiolocation service are determined by the mission of the system and vary widely even within a band; c) that ITU-R is considering the p
12、otential for the introduction of new types of systems or applications in bands between 420 MHz and 34 GHz used by radars in the radiodetermination service; d) that representative technical and operational characteristics of radars operating in the radiodetermination service are required to determine
13、 the feasibility of introducing new types of systems into frequency bands allocated to the radiodetermination service; e) that procedures and methodologies to analyse compatibility between radars in the radiodetermination service and systems in other services are contained in Recommendation ITU-R M.
14、1461, noting a) that this Recommendation along with Recommendation ITU-R M.1461 are used as a guideline in analysing compatibility between radiodetermination radars and systems in other services; b) that the criterion of interfering signal power to radar receiver noise power level are identified in
15、Recommendation ITU-R M.1461, recognizing a) that the required protection criteria depend upon the specific types of interfering signals; b) that the application of protection criteria may require consideration for inclusion of the statistical nature of the criteria and other elements of the methodol
16、ogy for performing compatibility studies (e.g. antenna scanning including motion of the transmitter and propagation loss). Further Rec. ITU-R M.1730-1 2 development of these statistical considerations may be incorporated into future revisions of this and other related Recommendations, as appropriate
17、, recommends 1 that the technical and operational characteristics of the radiolocation radars described in Annex 1 should be considered as representative of those operating or planned to operate in the band 15.4-17.3 GHz; 2 that an I/N ratio of 6 dB, should be used as the required protection level f
18、or the portions of the 15.4-17.3 GHz band where there is a radiolocation allocation and that this represents the net protection level if multiple interferers are present; 3 that in the case of pulsed interference, the criteria should be based on a case-by-case analysis taking into account the undesi
19、red pulse train characteristics and, to the extent possible, the signal processing in the radar receiver. NOTE 1 This Recommendation should be revised as more detailed information becomes available. Annex 1 Characteristics of and protection criteria for radars operating or planned to operate in the
20、radiolocation service in the frequency band 15.4-17.3 GHz 1 Introduction The characteristics of radiolocation radars operating or planned to operate worldwide in the frequency band 15.4-17.3 GHz are presented in Table 1 and described further in the following paragraphs. 2 Technical characteristics T
21、he band 15.4-17.3 GHz is used by many different types of radars including land-based, transportable, shipboard and airborne platforms. Radiolocation functions performed in the band include airborne and surface search, ground-mapping, terrain-following, maritime and target-identification. Radar opera
22、ting frequencies can be assumed to be uniformly spread throughout each radars tuning range. Table 1 contains technical characteristics of representative radiolocation radars deployed or planned to be deployed in the 15.4-17.3 GHz band. The major radiolocation radars operating or planned to operate i
23、n the band 15.4-17.3 GHz are primarily for detection of airborne objects and some are used for ground mapping. They are required to measure target altitude, range, bearing, and form terrain maps. Some of the airborne and ground targets are small and some are at ranges as great as 300 nautical miles
24、(556 km), so these radiolocation radars must have great sensitivity and must provide a high degree of suppression to all forms of clutter return, including that from sea, land and precipitation. Rec. ITU-R M.1730-1 3 TABLE 1 Characteristics of radiolocation radars in the 15.4-17.3 GHz band Character
25、istics System 1 System 2 System 3 System 4 System 5 System 6 Function Search, track and ground-mapping radar (multi-function) Search, track and ground-mapping radar (multi-function) Air surveillance, landing aid, track while scan Surveillance Ground surveillance and track Search, track and ground-ma
26、pping (multi-function) Platform type Airborne, low power Airborne, high power Shipboard, high power Ground-based, low power Ground-based, high power Airborne (typical operational height = 8 500 m) Tuning range (GHz) 16.2-17.3 16.29-17.21 15.7-17.3 16.21-16.5 15.7-16.2 15.4-17.3 Modulation Variable l
27、inear FM Linear FM pulse Pulse, frequency hopping Linear FM chirp Pulse, frequency hopping Linear FM chirp Transmit peak power (W) 80 700 20 k 2 10 k 500 Pulsewidth (s) 18.2; 49 120-443 0.1 5.5 36 0.05-50 Pulse rise/fall time (ns) 20 4 7/70 10 8 5-100 Pulse repetition rate (pps) 5 495; 2 041 900-1 6
28、00 4 000; 21 600 7 102 20 000 200-20 000 Maximum duty cycle 0.1 Not specified 0.00216 0.039 0.00072 Up to 0.2(1) Output device Travelling wave tube Travelling wave tube Travelling wave tube Transistor Travelling wave tube Travelling wave tube Antenna pattern type Fan/pencil Fan Pencil Pencil Pencil
29、Pencil Antenna type Slotted waveguide Phased array Planar phased array Elliptical with parabolic contour Double curved reflector with feed horn Phased array Antenna polarization Linear vertical Linear vertical RH circular Horizontal Circular Linear Antenna gain (dBi) 25.6 38.0 43.0 37.0 43 35 Antenn
30、a elevation beamwidth (degrees) 9.7 2.5 1 1.1 1.6 3.2 Antenna azimuthal beamwidth (degrees) 6.2 2.2 1 3.5 .25 3.2 Antenna horizontal scan rate 30 degrees/s 5 degrees/s 1 500 scans/min 7.8 or 15.6 degrees/s 60 rpm, 360 degrees/s 1-30 degrees/s Rec. ITU-R M.1730-1 4 TABLE 1 (end) Characteristics Syste
31、m 1 System 2 System 3 System 4 System 5 System 6 Antenna horizontal scan type (continuous, random, sector, etc.) 45 to 135 (mechanical) 30 (electronic, conical) 40 (mechanical) 180 (mechanical) 360 (continuous) 45 (electronic) Antenna vertical scan rate 30 degrees/s 5 degrees/s 1 500 scans/min Not a
32、pplicable Not applicable 1, 5 degrees/s Antenna vertical scan type 10 to 50 (mechanical) 0 to 90 (electronic, conical) +30/10 (mechanical) +22.5/33.75 (mechanical) Not applicable +5 to 45 (electronic) Antenna 1stside-lobe level 10 dBi at 31 18 dBi at 1.7 20 dBi at 1.6 15 dBi at 2.4 23 dBi at 1.6 3.5
33、 dB at 5.2 Antenna height Aircraft altitude Aircraft altitude Mast/deck mount Ground level 100 m Aircraft altitude 1st/2ndreceiver IF 3 dB bandwidths (MHz) 215/68 26.7 (wideband); 7.2 (narrow-band) 70/40 500/0.750 50 25 Receiver noise figure (dB) 4 2.7 Not specified 4 1 + (860/290) 860 = Receiver no
34、ise temperature K 290 = Earth noise temperature K 3.97 5 Minimum discernible signal (dBm) 89 97.4 80 100.4 92 100 Chirp bandwidth (MHz) 640 Not specified 30 0.750 Not specified 1 900(2) Transmitter RF emission bandwidth (MHz): 3 dB 20 dB 622; 271 725; 324 1 200; 600; 180 1 220; 620; 200 6.8; 37 20;
35、42 0.608 2.35 540 670 1 850 1 854 (1)Sharing studies will be conducted using multiple duty cycles from low duty cycles such as 0.01 to high duty cycles up to 0.2. (2)Sharing studies will focus on chirp bandwidths greater than 1 600 MHz. Rec. ITU-R M.1730-1 5 Largely because of these mission requirem
36、ents, the radiolocation radars using or planned to use the band 15.4-17.3 GHz tend to possess the following general characteristics: they tend to have high transmitter peak and average power, with notable exceptions; they typically use master-oscillator-power-amplifier transmitters rather than power
37、 oscillators. They are usually tuneable and some of them are frequency-agile. Some of them use linear-FM (chirp) or phase-coded intra-pulse modulation; some of them have antenna main beams that are steerable in both azimuth and elevation using electronic beam steering; they typically employ versatil
38、e receiving and processing capabilities, such as auxiliary side-lobe-blanking receive antennas, processing of coherent-carrier pulse trains to suppress clutter return by means of moving-target-indication, constant-false-alarm-rate techniques and, in some cases, adaptive selection of operating freque
39、ncies based on sensing of interference on various frequencies. Table 1 summarizes technical characteristics of representative systems deployed or planned to be deployed in the whole or portions of the band 15.4-17.3 GHz. This information is sufficient for general calculation to assess the compatibil
40、ity between these radars and other systems. Some or all of the radiolocation radars whose characteristics are presented in Table 1 possess the properties above, although they do not illustrate the full repertoire of attributes that might appear in future systems. 2.1 Transmitters The radars operatin
41、g or planned to operate in the 15.4-17.3 GHz band use a variety of modulations including unmodulated pulses, frequency-modulated (chirped) pulses and phase-coded pulses. Linear-beam and solid-state output devices are used in the final stages of the transmitters. The trend in new radar systems is tow
42、ard linear-beam and solid-state output devices due to the requirements of Doppler signal processing. Also, the radars deploying solid-state output devices have lower transmitter peak output power and higher pulse duty cycles. Typical transmitter RF emission (3 dB) bandwidths of radars operating or p
43、lanned to operate in the band 15.4-17.3 GHz range from 60 kHz to 1 850 MHz. Transmitter peak output powers range from 2 W (33.01 dBm) for solid-state transmitters to 20 kW (73.01 dBm) for high-power radars using crossed-field devices (magnetrons) and linear-beam (travelling wave tube) devices. 2.1.1
44、 Frequency hopping Frequency hopping is one of the most common electronic counter-counter-measures (ECCMs). Radar systems that are designed to operate in hostile electronic attack environments use frequency hopping as one of its ECCM techniques. This type of radar typically divides its allocated fre
45、quency band into channels. The radar then randomly selects a channel from all available channels for transmission. This random occupation of a channel can occur on a per beam position basis where many pulses on the same channel are transmitted, or on a per pulse basis. This important aspect of radar
46、 systems should be considered and the potential impact of frequency hopping radars should be taken into account in sharing studies. 2.2 Receivers The newer-generation radar systems use digital signal processing after detection for range, azimuth and Doppler processing. Generally, the signal processi
47、ng includes techniques that are used to enhance the detection of desired targets and to produce target symbols on the display. The signal-processing techniques used for the enhancement and identification of desired targets also provide 6 Rec. ITU-R M.1730-1 some suppression of low-duty-cycle (less t
48、han 5%) pulsed interference that is asynchronous with the desired signal. The signal processing in the newer generation of radars uses chirped and phase-coded pulses to produce a processing gain for the desired signal and may also provide suppression of undesired signals. Some of the newer low-power
49、 solid-state radars use high-duty-cycle (20%) multichannel signal processing to enhance the desired signal returns. Some radar receivers have the capability to identify RF channels that have low levels of undesired signals and command the transmitter to transmit on those RF channels. 2.3 Antennas A variety of different types of antennas are used on radars operating or planned to operate in the 15.4-17.3 GHz band. Antennas in this band are generally of a variety of sizes and thus are of interest for applications where mobility and li
