810-005, Rev. E
DSMS Telecommunications Link
Design Handbook
201
Frequency and Channel Assignments
Effective November 30, 2000
Document Owner: Approved by:
----------------------- -----------------------
C.J. Ruggier Date A. Kwok Date
Tracking System Engineer Tracking and Navigation Services
System Development Engineer
Prepared by: Released by:
[Signature on file in TMOD Library]
------------------------ ---------------------------
R.W. Sniffin Date TMOD Document Release Date
Change Log
Rev Issue Date Affected Paragraphs Change Summary
Initial 1/15/2001 All All
Note to Readers
There are two sets of document histories in the 810-005 document, and these
histories are reflected in the header at the top of the page. First, the entire document is
periodically released as a revision when major changes affect a majority of the modules. For
example, this module is part of 810-005, Revision E. Second, the individual modules also
change, starting as an initial issue that has no revision letter. When a module is changed, a
change letter is appended to the module number on the second line of the header and a summary
of the changes is entered in the module's change log.
This is a new module in Revision E of 810-005.
Contents
Paragraph Page
1 Introduction.......................................................................................... 4
1.1 Purpose and Scope................................................................................... 4
2 General Information................................................................................... 4
2.1 Tracking Modes of Operation......................................................................... 5
2.1.1 One-way........................................................................................... 5
2.1.2 Two-way........................................................................................... 5
2.1.3 Three-way......................................................................................... 5
2.1.4 Coherent Three-way............................................................................... 5
2.2 Spacecraft Transponder Turnaround Ratios............................................................ 5
2.3 Frequency Bands Allocated by the International Telecommunication Union (ITU)........................ 6
2.4 Deep Space Coherent Frequency Channels.............................................................. 7
Tables
Table Page
1. Spacecraft Transponder Turnaround Ratios............................................................. 6
2. Allocated Frequency Bands............................................................................ 6
3. Frequency and Channel Assignments for S-Band Uplink.................................................. 9
4. Frequency and Channel Assignments for X-Band Uplink................................................. 10
5. Frequency and Channel Assignments for Ka-Band Uplink............................................... 11
1 Introduction
1.1 Purpose and Scope
This module provides basic information about the frequencies that are
available in the Deep Space Network (DSN) and presents the way certain of the
DSN frequency allocations have been divided into channels. It does not specify
which stations can or will support assigned frequencies. That information is
contained in the appropriate Telecommunications Interfaces modules (101, 70-m
Antenna Subnet Telecommunications Interfaces; 102, 26-m Antenna Subnet
Telecommunications Interfaces; 103, 34-m HEF Antenna Subnet Telecommunications
Interfaces; or 104, 34-m BWG Stations Telecommunications Interfaces) of this
handbook. It also does not include propagation characteristics of the
frequencies. This information is provided in module 105 (Atmospheric and
Environmental Effects) and module 106 (Solar Corona and Solar Wind Effects) of
this handbook.
2 General Information
The DSN has developed channel plans to provide for orderly selection
and assignment of frequencies for deep-space missions (Category B, greater than
2 million km from Earth). (The DSN has not developed channel plans for near-
Earth missions [Category A, less than 2 million km from Earth].) The deep space
channel plans are based on bandwidth, hardware implementation, and transponder
turnaround-ratio considerations. The plans must allow phase coherent uplink
(Earth-to-space) and downlink (space-to-Earth) transmissions.
Through international agreements, the International Telecommunications
Union (ITU) allocates and regulates portions of the frequency spectrum for both
commercial and government use. The primary objective of the ITU is to establish
regulatory procedures for the coordinated use of frequencies by those agencies
permitted to operate in the allocated bands. The ITU has allocated certain bands
to deep space (Category B) research. In some cases, the deep space missions may
be required to conditionally share a frequency band between multiple users in
the same band.
The Consultative Committee for Space Data Systems (CCSDS) is an
international organization for space agencies interested in mutually developing
standard transmission and data handling techniques to support space research,
including space science and applications. As a member of the CCSDS, NASA has
submitted recommendations for various space systems applications. As an example,
the standard NASA Ka-band spacecraft transponder turnaround
ratio was first presented for review and approval to the CCSDS prior to its
implementation.
The National Telecommunications and Information Administration
(NTIA), an agency of the U.S. Department of Commerce, is the Executive
Branch's principal authority on domestic and international telecommunications
and information technology issues. During the planning phase of all missions
using the DSN, the proposed operating frequencies and other operating
parameters are reviewed by the NTIA for approval through the System Review
process. The NTIA evaluations are based upon the technical and regulatory
criteria for the efficient and coordinated use of the frequency spectrum by
NASA missions.
2.1 Tracking Modes of Operation
The following paragraphs describe the various ways in which the
telecommunications link can be configured for radio tracking. The source of
the uplink signal and the choice of references for measuring the received
frequency determine the mode of operation.
2.1.1 One-way
The spacecraft generates the downlink signal(s) from an onboard
oscillator. The DSN compares the received frequency against a locally
generated frequency.
2.1.2 Two-way
The DSN transmits a signal to the spacecraft. The spacecraft tracks
the phase of the uplink signal and generates a phase coherent downlink signal.
The DSN compares the received frequency with the same reference frequency from
which the uplink was generated.
2.1.3 Three-way
The spacecraft is tracked by two stations-one with the two-way mode
while the other receives and compares the signal to a locally generated
frequency. The most common application of this mode is during the handover
between stations at two different Deep Space Communication Complexes (DSCCs).
2.1.4 Coherent Three-way
Coherent three-way tracking is three-way tracking when the
transmitting and receiving stations share a common reference frequency.
2.2 Spacecraft Transponder Turnaround Ratios
To measure two-way or three-way Doppler shift, the spacecraft must
transmit a downlink signal that is phase coherent with the uplink signal. Table
1 provides the recommended spacecraft transponder turnaround ratios for various
uplink and downlink frequency bands. The tracking equipment at the DSN 34-m and
70-m stations can accommodate other turnaround ratios but this support must be
negotiated through the JPL Frequency Manager, who is resident in the Plans and
Commitments Program Office .
Table 1. Spacecraft Transponder Turnaround Ratios
Uplink Downlink Ratio (downlink/uplink)
S S 240/221
S X 880/221
S Ka 3344/221
X S 240/749
X X 880/749
X Ka 3344/749
Ka S 240/3599*
Ka X 880/3599*
Ka Ka 3344/3599*
* While these are the recommended ratios, all existing Ka-band
spacecraft have used turnaround ratios negotiated through the JPL
Frequency Manager.
Frequency Bands Allocated by the International
Telecommunication Union (ITU)
Frequency ranges have been allocated by the ITU for use in deep space
and near-Earth research. These ranges are listed in Table 2.
Table 2. Allocated Frequency Bands
Band Deep Space Bands (for spacecraft > 2 million km Near Earth Bands (for spacecraft < 2 million km from
Designation from Earth) Earth)
Uplink (Earth to Downlink (space to Earth) Uplink (Earth to Downlink (space to Earth)
space) space)
S-band 2110-2120 2290-2300 2025-2110 2200-2290
X-band 7145-7190 8400-8450 7190-7235 8450-8500
Ka-band 34200-34700 31800-32300
Deep Space Coherent Frequency Channels
The DSN has divided the frequency ranges allocated for deep space use
into channels for tracking support associated with a given transponder ratio.
The frequency ranges allocated for near-Earth uses do not have a formal
channelization plan. Tables 3, 4, and 5 list the 42-channel assignments by
frequency bands. Note that frequencies out of the allocated ranges for deep
space research are not shown in the tables.
The S-band downlink center frequency (F_ch(14) = 2295 MHz) is used to
derive all entries in the tables using the expressions
F_ch(n-1) = F_ch(n) - (10/27), rounded to the nearest hertz for n = 2 to
14
F_ch(n+1) = F_ch(n) + (10/27), rounded to the nearest hertz for n = 14
to 41
where F_ch(n) is the center frequency (in MHz) of channel n rounded
to the nearest Hz, and the ratio 10/27 is the spacing (in MHz) between the
centers of two adjacent channels.
Frequencies for other columns are derived by the procedure described
below. The calculated downlink frequencies may differ by 1 or 2 hertz between
the tables because each table assumes an integer uplink frequency and precise
turnaround ratios.
(1) The uplink frequency specified in the table is calculated from the
expression
F_ch(n)= F_ch(n) x TM/240, rounded to the nearest hertz,
where
F_ch(n) is the frequency of uplink channel n being calculated;
F_ch(n) is the frequency of channel n calculated for the S-band
downlink column
(including values for out-of-band channels); TM is the
transmit multiplier of a frequency band, that
is, TM = 221, 749, and 3599 for S uplink, X
uplink, and Ka uplink.
(2) The downlink frequencies specified in the table are calculated from
the expression F_ch(n) = F_ch(n) x TR, rounded to the nearest hertz,
where F_ch(n) is the frequency of channel n for the downlink columns;
F_ch(n) is the frequency of channel n in the uplink column;
TR is the turnaround ratio for the downlink frequency band as
provided in Table 1.
The DSN only supports two-way or three-way tracking with uplink and
downlink frequencies having the same channel number. Therefore, only channels 5
through 27 fully support coherent uplink and downlink for all frequency bands.
Channel 28, for example, supports S- or X-band uplink with coherent X- or Ka-
band downlink, but not with coherent S-band
downlink.
Before selecting operating frequencies or channels for a project,
the telecommunication designer should consult the JPL Frequency Manager, who
is resident in the Plans and Commitments Program Office
, to avoid frequency interference with
other spacecraft, present or planned.
Table 3. Frequency and Channel Assignments for S-band Uplink Table 4. Frequency
and Channel Assignments for X-band Uplink Table 5. Frequency and Channel
Assignments for Ka-band Uplink
Channel S-band U/L (MHz) S-band D/L (MHz) X-band D/L (MHz) Ka-band D/L (MHz)
5 2110.243056 2291.666667 8402.777780 31930.555562
6 2110.584105 2292.037037 8404.135803 31935.716050
7 2110.925154 2292.407407 8405.493826 31940.876538
8 2111.266204 2292.777778 8406.851853 31946.037042
9 2111.607253 2293.148148 8408.209876 31951.197530
10 2111.948303 2293.518519 8409.567903 31956.358033
11 2112.289352 2293.888889 8410.925927 31961.518521
12 2112.630401 2294.259259 8412.283950 31966.679009
13 2112.971451 2294.629630 8413.641977 31971.839512
14 2113.312500 2295.000000 8415.000000 31977.000000
15 2113.653549 2295.370370 8416.358023 31982.160488
16 2113.994599 2295.740741 8417.716050 31987.320991
17 2114.335648 2296.111111 8419.074073 31992.481479
18 2114.676697 2296.481481 8420.432097 31997.641967
19 2115.017747 2296.851852 8421.790124 32002.802470
20 2115.358796 2297.222222 8423.148147 32007.962958
21 2115.699846 2297.592593 8424.506174 32013.123462
22 2116.040895 2297.962963 8425.864197 32018.283950
23 2116.381944 2298.333333 8427.222220 32023.444438
24 2116.722994 2298.703704 8428.580248 32028.604941
25 2117.064043 2299.074074 8429.938271 32033.765429
26 2117.405092 2299.444444 8431.296294 32038.925917
27 2117.746142 2299.814815 8432.654321 32044.086420
28 2118.087191 8434.012344 32049.246908
29 2118.428241 8435.370371 32054.407411
30 2118.769290 8436.728395 32059.567899
31 2119.110339 8438.086418 32064.728387
32 2119.451389 8439.444445 32069.888891
33 2119.792438 8440.802468 32075.049379
Channel X-band U/L (MHz) S-band D/L (MHz) X-band D/L (MHz) Ka-band D/L (MHz)
1 7147.286265 2290.185185 31909.913580
2 7148.442131 2290.555556 31915.074083
3 7149.597994 2290.925926 8400.061729 31920.234571
4 7150.753857 2291.296296 8401.419752 31925.395059
5 7151.909723 2291.666667 8402.777779 31930.555562
6 7153.065586 2292.037037 8404.135802 31935.716050
7 7154.221449 2292.407407 8405.493825 31940.876538
8 7155.377316 2292.777778 8406.851853 31946.037042
9 7156.533179 2293.148148 8408.209877 31951.197530
10 7157.689045 2293.518519 8409.567903 31956.358033
11 7158.844908 2293.888889 8410.925927 31961.518521
12 7160.000771 2294.259259 8412.283950 31966.679009
13 7161.156637 2294.629630 8413.641977 31971.839512
14 7162.312500 2295.000000 8415.000000 31977.000000
15 7163.468363 2295.370370 8416.358023 31982.160488
16 7164.624229 2295.740741 8417.716050 31987.320991
17 7165.780092 2296.111111 8419.074073 31992.481479
18 7166.935955 2296.481481 8420.432097 31997.641967
19 7168.091821 2296.851852 8421.790123 32002.802470
20 7169.247684 2297.222222 8423.148147 32007.962958
21 7170.403551 2297.592593 8424.506175 32013.123462
22 7171.559414 2297.962963 8425.864198 32018.283950
23 7172.715277 2298.333333 8427.222221 32023.444438
24 7173.871143 2298.703704 8428.580248 32028.604941
25 7175.027006 2299.074074 8429.938271 32033.765429
26 7176.182869 2299.444444 8431.296295 32038.925917
27 7177.338735 2299.814815 8432.654321 32044.086420
28 7178.494598 8434.012345 32049.246908
29 7179.650464 8435.370372 32054.407411
30 7180.806327 8436.728395 32059.567899
31 7181.962190 8438.086418 32064.728387
32 7183.118057 8439.444446 32069.888891
33 7184.273920 8440.802469 32075.049379
34 7185.429783 8442.160493 32080.209867
35 7186.585649 8443.518520 32085.370370
36 7187.741512 8444.876543 32090.530858
37 7188.897378 8446.234570 32095.691361
Channel Ka-band U/L (MHz) S-band D/L (MHz) X-band D/L (MHz) Ka-band D/L (MHz)
1 34343.235337 2290.185185 31909.913578
2 34348.789359 2290.555556 31915.074080
3 34354.343365 2290.925926 8400.061729 31920.234569
4 34359.897372 2291.296296 8401.419752 31925.395058
5 34365.451394 2291.666667 8402.777779 31930.555560
6 34371.005401 2292.037037 8404.135802 31935.716049
7 34376.559407 2292.407407 8405.493826 31940.876538
8 34382.113429 2292.777778 8406.851853 31946.037040
9 34387.667436 2293.148148 8408.209876 31951.197529
10 34393.221458 2293.518519 8409.567903 31956.358031
11 34398.775465 2293.888889 8410.925926 31961.518520
12 34404.329471 2294.259259 8412.283950 31966.679009
13 34409.883493 2294.629630 8413.641977 31971.839511
14 34415.437500 2295.000000 8415.000000 31977.000000
15 34420.991507 2295.370370 8416.358023 31982.160489
16 34426.545529 2295.740741 8417.716050 31987.320991
17 34432.099535 2296.111111 8419.074074 31992.481480
18 34437.653542 2296.481481 8420.432097 31997.641969
19 34443.207564 2296.851852 8421.790124 32002.802471
20 34448.761571 2297.222222 8423.148147 32007.962960
21 34454.315593 2297.592593 8424.506174 32013.123462
22 34459.869599 2297.962963 8425.864198 32018.283951
23 34465.423606 2298.333333 8427.222221 32023.444440
24 34470.977628 2298.703704 8428.580248 32028.604942
25 34476.531635 2299.074074 8429.938271 32033.765431
26 34482.085641 2299.444444 8431.296295 32038.925920
27 34487.639663 2299.814815 8432.654322 32044.086422
28 34493.193670 8434.012345 32049.246911
29 34498.747692 8435.370372 32054.407414
30 34504.301699 8436.728395 32059.567902
31 34509.855705 8438.086419 32064.728391
32 34515.409727 8439.444446 32069.888894
33 34520.963734 8440.802469 32075.049382
34 34526.517741 8442.160492 32080.209871
35 34532.071763 8443.518519 32085.370373
36 34537.625769 8444.876543 32090.530862
37 34543.179791 8446.234570 32095.691365
38 34548.733798 8447.592593 32100.851853
39 34554.287805 8448.950616 32106.012342
40 34559.841827 32111.172845
41 34565.395833 32116.333333
42 34570.949840 32121.493822