1、Rec. ITU-R SM.1270 1 RECOMMENDATION ITU-R SM. 1270 ADDITIONAL INFORMATION FOR MONITORING PURPOSES RELATED TO CLASSIFICATION AND DESIGNATION OF EMISSION (Question ITU-R l/l) (1 997) The ITU Radiocommunication Assembly, considering that due to new techniques and technical capabilities the number of te
2、letype and other methods of that Article 25, No. 2055 (Article S19) of the Radio Regulations (RR) stipulates that: “All transmissions shall a) communication is increasing; b) be capable of being identified either by identification signals or by other means”; c) Recommendation ITU-R SM.1138 (RR Appen
3、dix 6, Part A) is sufficient for frequency management purposes; d) unambiguous and complete characterization of emissions, that the designation of emission in five characters mentioned in RR Article 4, Section Il (Article S4) and in that for monitoring purposes these five symbols for the classificat
4、ion of emission are inadequate for recommends that specified additional information should be collected by administrations on the different types of emissions; that a common database should be created at a place accessible to all monitoring services; that the structure of the database should be in a
5、ccordance with Annex 1, 1 2 3 ANNEX 1 Structure of the database Field name SYSTNUM SYSNAME TYPE ALPHABET BITS DET-COR MARK-CY REP-CY Type Length I 4 A 20 (Note 1) A 20 A 8 5 20 10 10 Description System number starting with 0001 common used system name like: SITOR, ROU-FEC, PACKET, TOR-342, etc. Syst
6、em type Possibilities: starstop burst type ARQ pulse train FEC twinplex SITOR multitone navigationlocation Used alphabet like ITA-2, SITOR, ITA-5 Number of bits per character Detectionkorrection system parity, marlspace ratio 3:4, etc. Mark cycle every 4,5 or 8 characters can be inverted to enable t
7、he receiver to synchronize. Repetition cycle If the receivers detects one or more corrupted characters it asks for repetition of a number of characters. STD-ITU-R RECMN SM.1270-ENGL 1777 = 4855232 0530087 332 2 Rec. ITU-R SM.1270 The following three fields can be used in case of multitone systems an
8、d twinplex si-tor. PULSE I 3 For multitone systems these fields can be 100/200/008 which means SEP 1 3 SEParation between tones 200 Hz NUMB I 3 NUMBer of tones: 8 PULSE duration 100 ms For twinplex si-tor systems these fields can be 200/280/5 10 which means that the separation betweenfi andfi = 200
9、Hz, between In both cases this information can often be enough to identi the country using this system without knowing the text of the messages. e.g. 1220-1 860 Hz In case of multitone systems the tones in use during an idling period. andfj = 280 Hz and betweenfj andf4 = 5 10 Hz BETWEEN A 10 In case
10、 of multitone systems the limits of the used tones IDLE A 10 For many systems there are a number of parameters depending on the baudspeed. If a system has the possibility to use different baudspeeds it is still the same system. Baudspeed dependent parameters must be stored in a second database with
11、a relation in a field of the first database. In this case that must be the field SYSTNUM. For every possible baudspeed of a particular system there must be a record in this second database. This database contains the following fields: Field name Type Length SYSTNUM I 4 BAUDSPEED D 832 AUTOCORR I 4 (
12、Note 1) BI T-D U R D 52 CYCLE I 4 INFO PAUSE CHAR I 4 I 4 I 3 Description System number for relation with the first database Baud speed of system, e.g. 164.35 Bd Peak of the auto correlation function, the number of bits in a character frame Duration of the bits, e.g. 10,30 ms Cycle time of the syste
13、m, time needed to transmit one character frame Time which CYCLE time contains information Time of CYCLE time without transmission Number of characters in one burst example: For a si-tor transmission CYCLEtime = 450ms INFO = 210ms PAUSE = 240ms CHAR =3 These databases will not cover all the possibilities. To create such a database is almost impossible, would be too complicated and does not meet the requirements of the monitoring engineer to have an easy to use and flexible tool. NOTE 1 - A: alphanumeric RR 1: numeric (integer) D: numeric (decimal)
