1、 Recommendation ITU-R M.2013 (01/2012) Technical characteristics of, and protection criteria for non-ICAO aeronautical radionavigation systems, operating around 1 GHz M Series Mobile, radiodetermination, amateur and related satellite services Rec. ITU-R M.2013 ii Foreword The role of the Radiocommun
2、ication Sector is to 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
3、 and policy functions 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/IT
4、U-R/ISO/IEC referenced 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/
5、ISO/IEC and the ITU-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) B
6、T Broadcasting service (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
7、fixed-satellite and 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 Pub
8、lication Geneva, 2012 ITU 2012 All rights reserved. No part of this publication may be reproduced, by any means whatsoever, without written permission of ITU. Rec. ITU-R M.2013 1 RECOMMENDATION ITU-R M.2013 Technical characteristics of, and protection criteria for non-ICAO aeronautical radionavigati
9、on systems, operating around 1 GHz (2012) Scope This Recommendation describes the technical characteristics of, and protection criteria for, non-International Civil Aviation Organisation (ICAO) aeronautical radionavigation service (ARNS) systems operating around 1 GHz for use in compatibility studie
10、s. It concerns with non-ICAO ARNS systems operating in countries referred to in RR No. 5.312 and TACAN systems. The ITU Radiocommunication Assembly, considering a) that the tactical air navigation system (TACAN) is an aeronautical radionavigation system used on a national basis and operates in the f
11、requency band 960-1 215 MHz; b) that the TACAN system is used by both civil and state aircraft; c) that when used by civil aviation, TACAN functionally is equivalent to the ICAO standardized distance measuring equipment (DME); d) that the TACAN system provides additional functionality to that of DME
12、, i.e. obtaining bearing information; e) that this additional functionality results in technical characteristics that differ from those of DME and may require additional consideration in future compatibility studies, f) that the use of TACAN also includes shipborne and air-to-air applications, notin
13、g a) that according to Resolution 417 (WRC-07) precedence must be given to the ARNS operating in the frequency band 960-1 164 MHz; b) that ITU-R studies have shown that following the introduction of aeronautical mobile (route) service (AM(R)S) in the frequency band 960-1 164 MHz, more detailed site-
14、specific compatibility studies between TACAN and AM(R)S systems need to be performed, recommends that for compatibility studies the characteristics and protection criteria in the annexes should be used. 2 Rec. ITU-R M.2013 Annex 1 Tactical air navigation system TACAN is an aeronautical radionavigati
15、on system used on a national basis operating between 960 and 1 215 MHz. A TACAN system consists of an interrogator on-board an aircraft and a beacon which gives the replies. In most cases the TACAN beacons are fixed ground based installations but there are maritime mobile and aeronautical mobile bea
16、cons in use as well. Depending on the generated e.i.r.p. and design of the interrogator slant ranges up to 400 nm (740 km) can be achieved but in practice the range is limited to the maximum radio line-of-sight (RLOS). The aircraft unit transmits regular pulse pairs, so-called interrogation pulses w
17、hich are received by ground based installations (beacons). The TACAN pulses have a pulse width of 3.5 s at the 50% amplitude points. The spacing between the pulses of an interrogation pulse pair is 12 s (X channel) or 36 s (Y channel). After receiving an interrogator pulse pair a ground station will
18、 test the pulse shape and spacing. If these fall within the acceptance limits, it will respond by transmitting a reply after a fixed delay with a 63 MHz frequency offset from the interrogation frequency depending on selected channel on pulse code. The beacon has a spacing between the reply pulses of
19、 12 s (X channel) and 30 s (Y channel). After receipt of the reply, the interrogator will calculate the momentary slant range distance to the beacon from the time elapsed between transmitting interrogation and receiving reply pulse pairs. The beacon will receive interrogations from many aircraft and
20、 therefore will send out many replies. Each interrogator creates a unique pattern by varying, within certain limits, the time between the pulse pairs to avoid generation of synchronic replies. By this principle each platform is able to recognize among all pulse pairs the replies that are initiated b
21、y its own interrogator. For identification purposes, a TACAN beacon transmits a Morse ID code. The ID tone is used at the airborne interrogators to verify if the range readouts are provided by the correct beacon. Besides the pulse responses, proper reception of the ID tone is also an important condi
22、tion for TACAN interrogators to properly function. In addition to the range measurements TACAN also offers azimuth bearing information. The bearing information is provided by applying a modulation in the amplitude of the pulses transmitted by the ground beacon. This pulse amplitude modulation (PAM)
23、is created using either a mechanically or electronically scanning beacon antenna. The variation in the azimuth pattern in the form of 15 Hz and 135 Hz antenna lobes at the maximum allowable modulation index of 55% will reduce the signal level of the reply pulses by up to 10.7 dB below the maximum e.
24、i.r.p. level of pulses without PAM. In order for the interrogator to decode the orientation of the antenna pattern in reference to north from the PAM, an additional 900 pulse pairs, consisting of a north-reference-pulse-group (NRPG) and additional fine reference pulse groups (RPG) are transmitted by
25、 the beacon. In order to obtain accurate bearing information and be able to reply to at least 100 aircraft with 70% reply efficiency a constant number of at least 3 600 pulse pairs have to be transmitted. The TACAN system is used for aeronautical navigation for both state aircraft as well as civil a
26、viation. When used by civil aviation, the TACAN equipment is functionally equivalent to the ICAO standardized DME. TACAN characteristics are given in Table 1. Rec. ITU-R M.2013 3 TABLE 1 Typical characteristics of TACAN stations Purpose Units Radio systems for air navigation (960-1 215 MHz) Radio tr
27、ansmission direction Earth-aircraft Aircraft-Earth Earth-aircraft maritime Aircraft-Earth maritime Aircraft aircraft Operating frequency range (MHz) 962-1 213 1 025-1 150 962-977 1 025-1 088 1 025-1 151 Operation range (limited to RLOS) (km) up to 600 up to 600 up to 600 up to 600 up to 740 Transmit
28、ted information Range and bearing response signals, Identification information Range and bearing request signal Range and bearing response signals, Identification Range and bearing request signal Range and bearing response signals, Identification Transmitter characteristics Station name Beacon Inter
29、rogator Beacon Interrogator Beacon Height above the ground (m) 3 (10 ft) up to 18 288 (60 000 ft) 3 (10 ft) up to 18 288 (60 000 ft) up to 18 288 (60 000 ft) Signal type Pulsed Pulsed Pulsed Pulsed Pulsed Channel spacing (MHz) 1 1 1 1 1 Type of modulation Pulse form and pulse pair spacing Pulse form
30、 and pulse pair spacing Pulse form and pulse pair spacing Pulse form and pulse pair spacing Pulse form and pulse pair spacing Transmitter power (pulsed) (dBW) 39 (max) 33 (max.) 39 (max) 33 (max) 33 (max) Pulse length (s) 3.5 0.5 (50% amplitude) 3.5 0.5 (50% amplitude) 3.5 0.5 (50% amplitude) 3.5 0.
31、5 (50% amplitude) 3.5 0.5 (50% amplitude) Typical duty factor (%) 2.52 0.105 2.52 0.105 0.735 Antenna type Circular array Omnidirectional Circular array Omnidirectional Circular array Typical antenna gain dBi 6 0 6 0 6 4 Rec. ITU-R M.2013 TABLE 1 (end) Purpose Units Radio systems for air navigation
32、(960-1 215 MHz) Receiver characteristics Receiving station Aircraft station Airport and en-route ground station Aircraft stations Maritime station Aircraft station Operating frequency range (MHz) 962-1 213 1 025-1 150 962-977 1 025-1 088 1 025-1 151 Height above the ground (m) up to 20 880 (60 000 f
33、t) 3 (10 ft) up to 20 880 (60 000 ft) 3 (10 ft) up to 20 880 (60 000 ft) Receiver 3 dB bandwidth (MHz) 2 2-4.5 2 2-4.5 2-4.5 Max/min antenna gain (dBi) 5.4/0 9.1/4.1 5.4/0 9.1/4.1 5.4/0 Polarization Vertical Vertical Vertical Vertical Vertical Receiver sensitivity (dBW) 122 122 122 122 122 Maximum a
34、cceptable interference level based on received power (dBW) 129 130 129 130 129 NOTE The protection ratios shown in Table 1 were obtained for non-pulsed signals. In case of pulsed signals it is required to carry out additional studies. In this respect signals with a pulse length of more than 50 s are
35、 considered non-pulsed or continuous signals. NOTE The airborne antenna gain is taken from Recommendation ITU-R M.1642-1. NOTE Measurements on some TACAN devices showed that the TACAN sensitivity for the distance and angular measurements only differ by 3 dB for the TACAN interrogator receiver (90 dB
36、m for distance and 87 dBm for angular measurement). Rec. ITU-R M.2013 5 There is a large installed base of TACAN equipment, both ground stations (beacons) as well as aircraft stations (interrogators), in various administrations. The actual technical characteristics of the various types of equipment
37、vary. One important factor, that determines the interference effect, is the receiver selectivity curve. Figure 1 shows the receiver selectivity curves of five types of TACAN interrogator equipment. It can be seen that there is a great spread in the selectivity of the different TACAN type receivers.
38、In the compatibility studies all TACAN type interrogators should be taken into account in order to guarantee sufficient protection of this aeronautical radionavigation service (ARNS) application including both range and azimuth determination functionality. Figure 2 shows a receiver selectivity curve
39、 for a typical TACAN beacon. The TACAN beacon selectivity is worse than those of the TACAN interrogator receivers. FIGURE 1 Airborne station (interrogator) receiver RF-selectivity curves F . 5- 1007- 0120 15 10 5 0 5 10 15 20F re que nc y o ffs e t (M H z )T A CA i nt e rrog a t or r e c e i ve r s
40、e l e c t i vi t y (i ndi c a t i ve )T A CA N i nt e rrog a t or t ype 1T A CA N i nt e rrog a t or t ype 2T A CA N i nt e rrog a t or t ype 4T A CA N i nt e rrog a t or t ype 5T A CA N i nt e rrog a t or t ype 3908060705030402001010Rejection(dB)6 Rec. ITU-R M.2013 FIGURE 2 Ground station (beacon)
41、receiver RF selectivity curves F . 5- 10 07 - 02T A CA N be a c on re c e i ve r RF -s e l e c t i vi t y 80 70 60 50 40 30 201000 2 4 6 8 10 12F re que nc y O ffs e t (M H z )Annex 2 Non-ICAO aeronautical radionavigation ystems operating in countries referred to in RR No. 5.312 Specifically the cou
42、ntries referred to in RR No. 5.312 of the Radio Regulations operate the aeronautical radionavigation systems of the following three types: Type 1: the ARNS systems of the first type refer to direction-finding and ranging systems. The systems are designed for finding an azimuth and a slant range of a
43、n aircraft as well as for area surveillance and inter-aircraft navigation. They are composed of airborne and ground-based stations. The airborne stations generate requesting signals transmitted via omnidirectional antennae and received at ARNS ground stations which also operate in an omnidirectional
44、 mode. The ground stations generate and transmit response signals containing azimuth/ranging information. Those signals are received and decoded at the ARNS airborne stations. The first type stations transmit the signals requesting the azimuth/ranging data outside the 960-1 164 MHz frequency band. A
45、fter receiving a requesting signal the ARNS ground stations use the 960-1 164 MHz frequency band only for transmitting the ranging data to be received at the ARNS airborne stations. Thus the ARNS systems of the first type use the 960-1 164 MHz frequency band only for transmitting the signals in the
46、surface-to-air direction. The maximum operation range for Rec. ITU-R M.2013 7 the first type ARNS systems is 400 km. It is expected that in some of the countries mentioned in RR No. 5.312 the usage of Type 1 of ARNS mentioned above may be discontinued. Type 2: the ARNS direction-finding and ranging
47、systems of the second type are designed for the same missions as the first type ARNS systems. The primary difference of the second type stations refers to the fact that requesting signals are transmitted by the airborne stations in the same frequency band as responding signals transmitted from the g
48、round stations. Moreover, the ground-based ARNS stations of the second type can operate in both directional and omnidirectional modes. Directional mode provides increased number of operational channels at the ARNS stations. The maximum operation range for the first type ARNS systems is 400 km. It is
49、 planned to use the overall frequency band 960-1 164 MHz allocated to the ARNS in order to increase flexibility of operation of the second type ARNS systems. Application of the wideband tuning filter on the ARNS receiver front end is the design peculiarity of the second type ARNS systems which is stipulated by the necessity to receive signals on several channels simultaneously. The 3 dB bandwidth of this filter is 22 MHz and it allows receiving simultaneously up to five channels among 30 overlapping channels of 4.3 MHz each. The
