Collapse to view only § 2.201 - Emission, modulation, and transmission characteristics.
§ 2.201 - Emission, modulation, and transmission characteristics.
The following system of designating emission, modulation, and transmission characteristics shall be employed.
(a) Emissions are designated according to their classification and their necessary bandwidth.
(b) Three symbols are used to describe the basic characteristics of emissions. Emissions are classified and symbolized according to the following characteristics:
(1) First symbol—type of modulation of the main carrier;
(2) Second symbol—nature of signal(s) modulating the main carrier;
(3) Third symbol—type of information to be transmitted.
Note to paragraph (Two additional symbols for the classification of emissions may be added for a more complete description of an emission. See Appendix 1, Sub-Section IIB of the ITU Radio Regulations for the specifications of these fourth and fifth symbols. Use of these symbols is not required by the Commission.
(c) First Symbol—types of modulation of the main carrier:
(1) Emission of an unmodulated carrier | N | (2) Emission in which the main carrier is amplitude-modulated (including cases where sub-carriers are angle-modulated): | —Double-sideband | A | —Single-sideband, full carrier | H | —Single-sideband, reduced or variable level carrier | R | —Single-sideband, suppressed carrier | J | —Independent sidebands | B | —Vestigial sideband | C | (3) Emission in which the main carrier is angle-modulated: | —Frequency modulation | F | —Phase modulation | G |
Whenever frequency modulation “F” is indicated, Phase modulation “G” is also acceptable.
(4) Emission in which the main carrier is amplitude and angle-modulated either simultaneously or in a pre-established sequence | D | (5) Emission of pulses: 1 | —Sequence of unmodulated pulses | P | —A sequence of pulses: | —Modulated in amplitude | K | —Modulated in width/duration | L | —Modulated in position/phase | M | —In which the carrier is angle-modulated during the period of the pulse | Q | —Which is a combination of the foregoing or is produced by other means | V | (6) Cases not covered above, in which an emission consists of the main carrier modulated, either simultaneously or in a pre-established sequence, in a combination of two or more of the following modes: amplitude, angle, pulse | W | (7) Cases not otherwise covered | X |
1 Emissions where the main carrier is directly modulated by a signal which has been coded into quantized form (e.g. pulse code modulation) should be designated under (2) or (3).
(d) Second Symbol—nature of signal(s) modulating the main carrier:
(1) No modulating signal | 0 | (2) A single channel containing quantized or digital information without the use of a modulating sub-carrier, excluding time-division muliplex | 1 | (3) A single channel containing quantized or digital information with the use of a modulating sub-carrier, excluding time-division multiplex | 2 | (4) A single channel containing analogue information | 3 | (5) Two or more channels containing quantized or digital information | 7 | (6) Two or more channels containing analogue information | 8 | (7) Composite system with one or more channels containing quantized or digital information, together with one or more channels containing analogue information | 9 | (8) Cases not otherwise covered | X |
(e) Third Symbol—type of information to be transmitted:
2
2 In this context the word “information” does not include information of a constant, unvarying nature such as is provided by standard frequency emissions, continuous wave and pulse radars, etc.
(1) No information transmitted | N | (2) Telegraphy—for aural reception | A | (3) Telegraphy—for automatic reception | B | (4) Facsimile | C | (5) Data transmission, telemetry, telecommand | D | (6) Telephony (including sound broadcasting) | E | (7) Television (video) | F | (8) Combination of the above | W | (9) Cases not otherwise covered | X |
(f) Type B emission: As an exception to the above principles, damped waves are symbolized in the Commission's rules and regulations as type B emission. The use of type B emissions is forbidden.
(g) Whenever the full designation of an emission is necessary, the symbol for that emission, as given above, shall be preceded by the necessary bandwidth of the emission as indicated in § 2.202(b)(1).
§ 2.202 - Bandwidths.
(a) Occupied bandwidth. The frequency bandwidth such that, below its lower and above its upper frequency limits, the mean powers radiated are each equal to 0.5 percent of the total mean power radiated by a given emission. In some cases, for example multichannel frequency-division systems, the percentage of 0.5 percent may lead to certain difficulties in the practical application of the definitions of occupied and necessary bandwidth; in such cases a different percentage may prove useful.
(b) Necessary bandwidth. For a given class of emission, the minimum value of the occupied bandwidth sufficient to ensure the transmission of information at the rate and with the quality required for the system employed, under specified conditions. Emissions useful for the good functioning of the receiving equipment as, for example, the emission corresponding to the carrier of reduced carrier systems, shall be included in the necessary bandwidth.
(1) The necessary bandwidth shall be expressed by three numerals and one letter. The letter occupies the position of the decimal point and represents the unit of bandwidth. The first character shall be neither zero nor K, M or G.
(2) Necessary bandwidths:
between 0.001 and 999 Hz shall be expressed in Hz (letter H); between 1.00 and 999 kHz shall be expressed in kHz (letter K); between 1.00 and 999 MHz shall be expressed in MHz (letter M); between 1.00 and 999 GHz shall be expressed in GHz (letter G).(3) Examples:
0.002 Hz—H002 0.1 Hz—H100 25.3 Hz—25H3 400 Hz—400H 2.4 kHz—2K40 6 kHz—6K00 12.5 kHz—12K5 180.4 kHz—180K 180.5 kHz—181K 180.7 kHz—181K 1.25 MHz—1M25 2 MHz—2M00 10 MHz—10M0 202 MHz—202M 5.65 GHz—5G65(c) The necessary bandwidth may be determined by one of the following methods:
(1) Use of the formulas included in the table, in paragraph (g) of this section, which also gives examples of necessary bandwidths and designation of corresponding emissions;
(2) For frequency modulated radio systems which have a substantially linear relationship between the value of input voltage to the modulator and the resulting frequency deviation of the carrier and which carry either single sideband suppressed carrier frequency division multiplex speech channels or television, computation in accordance with provisions of paragraph (f) of this section and formulas and methods indicated in the table, in paragraph (g) of this section;
(3) Computation in accordance with Recommendations of the International Radio Consultative Committee (C.C.I.R.);
(4) Measurement in cases not covered by paragraph (c) (1), (2), or (3) of this section.
(d) The value so determined should be used when the full designation of an emission is required. However, the necessary bandwidth so determined is not the only characteristic of an emission to be considered in evaluating the interference that may be caused by that emission.
(e) In the formulation of the table in paragraph (g) of this section, the following terms are employed:
B(f) Determination of values of D and B
(1) Determination of D in systems for multichannel telephony:
(i) The rms value of the per-channel deviation for the system shall be specified. (In the case of systems employing preemphasis or phase modulation, this value of per-channel deviation shall be specified at the characteristic baseband frequency.)
(ii) The value of D is then calculated by multiplying the rms value of the per-channel deviation by the appropriate factors, as follows:
Number of message circuits | Multiplying factors | Limits of X (P | More than 3, but less than 12 | 4.47 × [a factor specified by the equipment manufacturer or station licensee, subject to Commission approval] | 3.76 antilog (X + 2 log | At least 12, but less than 60 | ————————————— | X: −2 to + 2.6. | 20 | 3.76 antilog (X + 4 log | At least 60, but less than 240 | ————————————— | X: −5.6 to −1.0. | 20 | 3.76 antilog (X + 10 log | 240 or more | ————————————— | X: −19.6 to −15.0. | 20 |
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Where X represents the average power in a message circuit in dBmO; N
(2) The necessary bandwidth (B
(i) 2M + 2DK, for systems having no continuity pilot subcarrier or having a continuity pilot subcarrier whose frequency is not the highest modulating the main carrier;
(ii) 2P + 2DK, for systems having a continuity pilot subcarrier whose frequency exceeds that of any other signal modulating the main carrier, unless the conditions set forth in paragraph (f)(3) of this section are met.
(3) As an exception to paragraph (f)(2)(ii) of this section, the necessary bandwidth (B
(i) The modulation index of the main carrier due to the continuity pilot subcarrier does not exceed 0.25, and
(ii) In a radio system of multichannel telephony, the rms frequency deviation of the main carrier due to the continuity pilot subcarrier does not exceed 70 percent of the rms value of the per-channel deviation, or, in a radio system for television, the rms deviation of the main carrier due to the pilot does not exceed 3.55 percent of the peak deviation of the main carrier.
(g) Table of necessary bandwidths:
Description of emission | Necessary bandwidth | Designation of emission | Formula | Sample calculation | Continuous wave emission | N0N (zero) | 1. Signal With Quantized or Digital Information | Continuous wave telegraphy | B | 25 words per minute; B = 20, K = 5, Bandwidth: 100 Hz | 100HA1A | Telegraphy by on-off keying of a tone modulated carrier | B | 25 words per minute; B = 20, M = 1000, K = 5, Bandwidth: 2100 Hz = 2.1 kHz | 2K10A2A | Selective calling signal, single-sideband full carrier | B | Maximum code frequency is: 2110 Hz, M = 2110, Bandwidth: 2110 Hz = 2.11 kHz | 2K11H2B | Direct-printing telegraphy using a frequency shifted modulating sub-carrier single-sideband suppressed carrier | B | B = 50, D = 35 Hz (70 Hz shift), K = 1.2, Bandwidth: 134 Hz | 134HJ2B | Telegraphy, single sideband reduced carrier | B | 15 channels; highest central frequency is: 2805 Hz, B = 100, D = 42.5 Hz (85 Hz shift), K = 0.7 Bandwidth: 2.885 Hz = 2.885 kHz | 2K89R7B | 2. Telephony (Commercial Quality) | Telephony double-sideband | B | M = 3000, Bandwidth = 6000 Hz = 6 kHz | 6K00A3E | Telephony, single-sideband, full carrier | B | M = 3000, Bandwidth: 3000 Hz = 3 kHz | 3K00H3E | Telephony, single-sideband suppressed carrier | B | M = 3000, lowest modulation frequency is 3000 Hz, 2700 Hz Bandwidth: 2700Hz = 2.7 kHz | 2K70J3E | Telephony with separate frequency modulated signal to control the level of demodulated speech signal, single-sideband, reduced carrier | B | Maximum control frequency is 2990 Hz, M = 2990, Bandwidth: 2990 Hz = 2.99 kHz | 2K99R3E | Telephony with privacy, single-sideband, suppressed carrier (two or more channels) | B | N | 5K75J8E | Telephony, independent sideband (two or more channels) | B | 2 channels, M = 3000, Bandwidth: 6000 Hz = 6 kHz | 6K00B8E | 3. Sound Broadcasting | Sound broadcasting, double-sideband | B | Speech and music, M = 4000, Bandwidth: 8000 Hz= 8 kHz | 8K00A3E | Sound broadcasting, single-sideband reduced carrier (single channel) | B | Speech and music, M = 4000, Bandwidth: 4000 Hz= 4 kHz | 4K00R3E | Sound broadcasting, single-sideband, suppressed carrier | B | Speech and music, M = 4500, lowest modulation frequency = 50 Hz, Bandwidth: 4450 Hz = 4.45 kHz | 4K45J3E | 4. Television | Television, vision and sound | Refer to CCIR documents for the bandwidths of the commonly used television systems | Number of lines = 525; Nominal video bandwidth: 4.2 MHz, Sound carrier relative to video carrier = 4.5 MHz | 5M75C3F | Total vision bandwidth: 5.75 MHz; FM aural bandwidth including guardbands: 250,000 Hz | 250KF3E | Total bandwidth: 6 MHz | 6M25C3F | 5. Facsimile | Analogue facsimile by sub-carrier frequency modulation of a single-sideband emission with reduced carrier | B | N = 1100, corresponding to an index of cooperation of 352 and a cycler rotation speed of 60 rpm. Index of cooperation is the product of the drum diameter and number of lines per unit length C = 1900, D = 400 Hz, Bandwidth = 2.890 Hz = 2.89 kHz | 2K89R3C | Analogue facsimile; frequency modulation of an audio frequency sub-carrier which modulates the main carrier, single-sideband suppressed carrier | B | N = 1100, D = 400 Hz, Bandwidth: 1980 Hz = 1.98 kHz | 1K98J3C | 6. Composite Emissions | Double-sideband, television relay | B | Video limited to 5 MHz, audio on 6.5 MHz frequency modulated subcarrier deviation = 50 kHz: C = 6.5 × 10 6 D = 50 × 10 3 Hz, M = 15,000, Bandwidth: 13.13 × 10 6 Hz = 13.13 MHz | 13M2A8W | Double-sideband radio relay system | B | 10 voice channels occupying baseband between 1 kHz and 164 kHz; M = 164,000 bandwith = 328,000 Hz = 328 kHz | 328KA8E | Double-sideband emission of VOR with voice (VOR = VHF omnidirectional radio range) | B | The main carrier is modulated by: —a 30 Hz sub-carrier—a carrier resulting from a 9960 Hz tone frequency modulated by a 30 Hz tone—a telephone channel—a 1020 Hz keyed tone for continual Morse identification. C | 20K9A9W | Independent sidebands; several telegraph channels together with several telephone channels | B | Normally composite systems are operated in accordance with standardized channel arrangements, (e.g. CCIR Rec. 348-2) 3 telephone channels and 15 telegraphy channels require the bandwidth 12,000 Hz = 12 kHz | 12K0B9W | 1. Signal With Quantized or Digital Information | Telegraphy without error-correction (single channel) | B | B = 100, D = 85 Hz (170 Hz shift), Bandwidth: 304 Hz | 304HF1B | Four-frequency duplex telegraphy | B | Spacing between adjacent frequencies = 400 Hz; Synchronized channels; B = 100, M = 50, D = 600 Hz, Bandwidth: 1420 Hz = 1.42 kHz | 1K42F7B | 2. Telephony (Commercial Quality) | Commercial telephony | B | For an average case of commercial telephony, M = 3,000, Bandwidth: 16,000 Hz = 16 kHz | 16K0F3E | 3. Sound Broadcasting | Sound broadcasting | B | Monaural, D = 75,000 Hz, M = 15,000, Bandwidth: 18,000 Hz = 180 kHz | 180KF3E | 4. Facsimile | Facsimile by direct frequency modulation of the carrier; black and white | B | N = 1100 elements/sec; D = 400 Hz, Bandwidth: 1980 Hz = 1.98 kHZ | 1K98F1C | Analogue facsimile | B | N = 1100 elements/sec; D = 400 Hz, Bandwidth: 1980 Hz = 1.98 kHz | 1K98F3C | 5. Composite Emissions (See Table III-B) | Radio-relay system, frequency division multiplex | B | Microwave radio relay system specifications: 60 telephone channels occupying baseband between 60 and 300 kHz; rms per-channel deviation 200 kHz; pilot at 331 kHz produces 200 kHz rms deviation of main carrier. Computation of B | 2M45F8E | Radio-relay system frequency division multiple | B | Microwave radio relay relay systems specifications: 1200 telephone channels occupying baseband between 60 and 5564 kHz; rms per channel deviation 200 kHz; continunity pilot at 6199 kHz produces 140 kHz rms deviation of main carrier. Computation of B | 16M6F8E | Radio-relay system, frequency division multiplex | B | Microwave radio relay system specifications: Multiplex 600 telephone channels occupying baseband between 60 and 2540 kHz; continuity pilot at 8500 kHz produces 140 kHz rms deviation of main carrier. Computation of Bn:D = (200 × 10 3 × 3.76 × 2.565) = 1.93 × 10 6 Hz; M = 2.54 × 10 6 Hz; 2DK)≤2P Bandwidth: 17 × 10 6 Hz | 17M0F8E | Unmodulated pulse emission | B | Primary Radar Range resolution: 150 m, K = 1.5 (triangular pulse where t≃t | 3M00P0N | 6. Composite Emissions | Radio-relay system | B | Pulse position modulated by 36 voice channel baseband; pulse width at half amplitude = 0.4 us, Bandwidth: 8 × 10 6 Hz = 8 MHz (Bandwidth independent of the number of voice channels) | 8M00M7E | Radio-relay system | B K = 1.6 | Pulse position modulated by 36 voice channel baseband: pulse width at half amplitude 0.4 μS; B | 8M00M7E | Composite transmission digital modulation using DSB-AM (Microwave radio relay system) | B | Digital modulation used to send 5 megabits per second by use of amplitude modulation of the main carrier with 4 signaling states
R = 5 × 10 6 bits per second; K = 1; S = 4; B | 5M00K7 | Binary Frequency Shift Keying | (0.03 <2D/R <1.0);
B (1.0 <2D/R <2) B | Digital modulation used to send 1 megabit per second by frequency shift keying with 2 signaling states and 0.75 MHz peak deviation of the carrier
R = 1 × 10 6 bps; D = 0.75 × 10 6 Hz; B | 2M80F1D | Multilevel Frequency Shift Keying | B | Digital modulation to send 10 megabits per second by use of frequency shift keying with four signaling states and 2 MHz peak deviation of the main carrier
R = 10 × 10 6 bps; D = 2 MHz; K = 1; S = 4; B | 9M00F7D | Phase Shift Keying | B | Digital modulation used to send 10 megabits per second by use of phase shift keying with 4 signaling states
R = 10 × 10 6 bps; K = 1; S = 4; B | 10M0G7D | Quadrature Amplitude Modulation (QAM) | B | 64 QAM used to send 135 Mbps has the same necessary bandwidth as 64-PSK used to send 135 Mbps;
R = 135 × 10 6 bps; S = 64; B | 45M0W | Minimum Shift Keying | 2-ary:
B 4-ary: B | Digital modulation used to send 2 megabits per second using 2-ary minimum shift keying
R = 2.36 × 10 6 bps; B | 2M36G1D |
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