Block VI

Question 1

What is Electromagnetic Interference (EMI)?

Answer 1

Any electromagnetic disturbance which interrupts, obstructs, or otherwise
degrades or limits the effective performance of electronics/electrical equipment.
EMI can be intentional, as in some forms of electronic warfare, or unintentional
as a result of spurious emission responses, Intermodulation products and the
like. In addition, EMI can be a naturally occurring phenomena when the
electromagnetic field of one device disrupts, impedes or degrades the
electromagnetic field of another device by coming into proximity with it.

Question 2

Most interference is caused by…?

Answer 2

friendlies (blue on blue)

Question 3

There are two main types of interference:

Answer 3

Downlink Interference: the part of the transmission lin reaching from the satellite to the ground. This can be caused by natural phenomena, misconfigured equipment, nearby sources and/or adversaries.

Uplink Interference: the part of the transmission link from the earth station to the satellite. This can be caused by natural phenomena, misconfigured equipment, nearby sources and/or adversaries.

Question 4

This may produce EMI including variations in ionosphere properties, radio noise bursts from t he sun, flares from the sun and terrestrial atmospheric effects such as high rain rates.

Answer 4

Natural phenomena

Question 5

These are solar radio bursts or noise storms; rain attenuation.

Answer 5

SHF natural sources

Question 6

How do you resolve solar radio EMI?

Answer 6

determine if link LOS is aligned with the sun and if the side lobes of antennae intersect the sun’s radio output. Real-time and
forecast space and terrestrial weather data and products may be obtained from
AFWA (Air Force Weather Agency), which addresses both sources described above.

Question 7

What can you do if experiencing downlink inteference?

Answer 7

Have the terminal experiencing interference check all their equipment to include the offline equipment for unexpected configurations. Equipment could be
incorrectly patched or configured causing their issues. Also, have the terminal
survey their antenna pointing direction to ensure there are no obstructions or
equipment capable of emitting signals in the path.

Our operating bands are popular with radar and there have been issues caused
by police running radar and collocated radar stations in the past.

Question 8

This is interference caused by a planned signal on
the same channel. For instance, SBR1-3 and SBR3-3 contain the exact same frequencies but are typically separated geographically. If there is a transmitter
on the edge of both beams, then their signal would show up in both coverage areas creating interference for the channel it is not planned in.

(same channel - different beam)

Answer 8

Co-Channel Interference (CCI)

Question 9

This is interference that comes from a signal not planned in the same frequency but operating nearby. For example, if two carriers are planed side by side (8103 MHz, 8104 MHz) and one of them raises
power they can cause interference with the signal they are next to.

Answer 9

Adjacent Channel Interference (ACI)

Question 10

What are two types of interference common with uplink?

Answer 10

CCI and ACI

Question 11

If interference persists after ruling out CCI and ACI, we need to attempt to isolate the terminal responsible. This involves contacting all terminals in the coverage area to check their equipment to ensure they are not emitting the signal. This is known as…?

Answer 11

Roll Call

Question 12

EMI can present itself in a variety of forms. There are four common forms. The following describes which of the four common characteristics?

The signal is persistent and unchanging

Answer 12

Constant

Question 13

EMI can present itself in a variety of forms. There are four common forms. The following describes which of the four common characteristics?

The signal does not change other than its presence is not persistent.

Answer 13

Intermittent

Question 14

EMI can present itself in a variety of forms. There are four common forms. The following describes which of the four common characteristics?

The signal is changing frequencies across the spectrum.

Answer 14

Sweeping

Question 15

EMI can present itself in a variety of forms. There are four common forms. The following describes which of the four common characteristics?

The signal is changing power levels.

Answer 15

Pulsing

Question 16

There are three main ways we identify EMI. What are they?

Answer 16

1. WRMS Alarms - WRMS can generate alarms when it detects EMI.
2. Visually through WRMS - WRMS cannot detect all instances of EMI. As the TC, you are responsible for visually scanning the spectrum presented by WRMS for any anomalous signals.
3. User reports - users can cal to inform the WSOC that they are experiencing interference.

Question 17

What is step 1 of initial actions of EMIs?

Answer 17

1. TC upon notification of interference from a user or receiving an aalrm indicating an EMI will notify the CCH

Question 18

What is step 2 of initial actions of EMIs?

Answer 18

2. CCH will direct controller to continue with an initial assessment of the EMI and another controller to
   review CNPS/WRMS for the following:

• The EMI is not an ENDEXED Mission that has not de-accessed
• Use the Search Workspace Tree options to check CNPS for the center frequency for MHz only (i.e.,
  8,354 MHz and not 8,354.213 MHz) of the ±5 MHz in 1-MHz steps (9 inquires) from the center
  frequency on the impacted satellite or another satellite within 6 degrees of the impacted satellite and
  identify all potential EMI contributors
• WRMS is on the correct Epoch; Ensure alarm definitions are set to the current EPOCH (i.e., it is a new
  mission that has not been incorporated and/or disseminated)
• The EMI is not Co-Channel Interference (CCI)
• A new mission accessing early

Question 19

What is step 3 of initial actions of EMIs?

Answer 19

3. TC confirm any impact as a result of the EMI with the user

Question 20

What is step 4 of initial actions of EMIs?

Answer 20

4. TC Using WRMS and CNPS, determine the following:

• What transmit beam the user is in
• Any other terminals in the transmit beam
• Check for past, present, or future mission at EMI frequency
• What receive beam the appropriate sub channels are routed to, if any

Question 21

What is step 5 of initial actions of EMIs?

Answer 21

5. CCH Coordinate with the WPC to review GSCCE sub-channel plot, capture access time, continue
   monitoring, and provide updates

Question 22

What is step 6 of initial actions of EMIs?

Answer 22

6. TC Observe the spectrum for any visible EMI indications; Verify that the alternate WSOC is also seeing the EMI*. If it is, continue. If the alternate site does not see the EMI check for local interference. EMI on the Space Craft isn’t likely at this point but not 100% ruled out. Check to see what the PC sees; Notify the CCH of the intent to continue interference assessment

Question 23

What is step 7 of initial actions of EMIs?

Answer 23

7. TC Upon completing initial assessment of the EMI impacting WGS or DSCS operations, report the
   information to the WBWO and RSSC

*** THE ALTERNATE WRMS BOX SHOULD BE GEOGRAPHICALLY SEPERATED FROM THE PRIMARY BOX, OTHERWISE THEY WILL ALWAYS BOTH SEE THE SAME RESULTS.

Question 24

What is step 8 of initial actions of EMIs?

Answer 24

8. TC For WGS EMI, using WRMS and GSCCE gives the best indications of U/L or D/L EMI (check power
   level changes; is it varying or pulsing; slow increase or decrease). If it is determined the EMI is on the satellite (U/L), proceed to step 11

For DSCS EMI, it is possible that a WSOC or RMCE Site is not in-beam and will not be able to see uplink
EMI on WRMS

Question 25

What is step 9 of initial actions of EMIs?

Answer 25

9. TC Coordinate with in-beam terminals that are geographically separated to determine if they can see the EMI

Question 26

What is step 10 of initial actions of EMIs?

Answer 26

10. TC If other terminals can see the EMI, assume the EMI is on the satellite and proceed to step 12

Question 27

What is step 11 of initial actions of EMIs?

Answer 27

11. TC If no other terminals can see the EMI, assume the EMI is local (downlink) and proceed to step 24

Question 28

What is step 12 of initial actions of EMIs?

Answer 28

12. TC Characterize the EMI with all available information to include modulation, coding, bandwidth, center frequency, amplitude, data rate, power level, time of access, and any other characteristics of the signal

Question 29

How soon must an uplink EMI be reported?

Answer 29

1. If occupying allocated bandwidth - immediately 2. If occupying unallocated bandwidth - within 15 minutes

Question 30

How are EMIs reported?

Answer 30

The initial quicklook will contain the characterization data provided by the TC and the reported to the CCH who will submit the quicklook.

Question 31

Before conducting roll call, what are some factors you should include when it comes to possible uplink EMIs?

Answer 31

- Determine if the EMI occurred during a new mission access, upon completion of a database download, during a terminal’s authorized or emergency outage, after satellite commanding, or during a satellite anomaly (Task to an alternate TC, if available, while continuing to work the process) - Coordinate with other WSOCs to determine if a terminal has accessed the wrong satellite using an authorized SAA frequency - Clear in-house WSOC equipment ensuring the EMI is not being transmitted from the WSOC

Question 32

What is the process for dealing with an uplink EMI after ruling out any other potential reasons for the interference?

Answer 32

1. TC Coordinate with the WBWO to ensure the Directive Gain Excel workbook was updated after the DTG of the most recent Ops Config for the affected IRON 2. TC Save the Directive Gain Excel workbook located at: \\cws1fs\User Data\CWS_DFS_NEW\Watch Officer\Tools-Procedures\Directive Gains.xlsx in accordance with local SOP to the site specific EMI folder on WSOMS to be used as the roll call workbook 3. TC Open the roll call workbook and Click on the filter arrow in the “satellite_identifier” column, uncheck “Select All”, and select the appropriate IRON, and click “OK” 4. TC Click on the filter arrow in the “antenna_identifier” column, uncheck “Select All”, and select the appropriate antenna(s), and click “OK” 5. TC Click on the filter arrow in the “frequency_band” column, uncheck “Select All”, and select the appropriate band, and click “OK” 6. TC Click on the filter arrow in the “Threshold” column and click “Sort Largest to Smallest” 7. TC Click the Save icon in the upper left corner NOTE: ENSURE YOU ARE NOT SAVING OVER THE WBWO DIRECTIVE GAIN WORKBOOK. 8. TC Direct all terminals with a threshold greater than or equal to 80 to check transmitter output with a spectrum analyzer (IAW site SOP) 9. TC When attempting to contact a terminal in the Roll Call, document the phone number used in the “Contact_Number” Column 10. TC If positive contact is made with a competent terminal operator who confirms they performed the requested procedure, document the terminal operator’s CHOPS in the “Tml_Chops” column and put “Yes” into the “Positive_Control” column for that terminal in the Roll Call. If negative contact (i.e., no answer or unable to perform the requested procedure), put “No” into the “Positive_Control” column for that terminal in the Roll Call. NOTE: A COMPLETED ROLL CALL IS HAVING POSITIVE CONTROL WITH AT LEAST 85% AND AN ATTEMPT MADE WITH 100% OF THE TERMINALS AND A THRESHOLD OF 80% OR GREATER. 11. TC Document the response from all terminals and provide this data to the CCH 12. TC If terminals are unable to check their equipment, coordinate with the WBWO for alternative methods (e.g., power raise) to determine if they are transmitting the EMI 13. TC If a terminal indicates that they are transmitting the EMI, coordinate with the terminal to get them to stop transmitting the EMI NOTE: IF THE EMI IS NOT AFFECTING USERS AND REQUIRES THE USER TO DE-ACCESS TO STOP THE EMI, COORDINATE THIS ACTION WITH THE WBWO. AT NO TIME WILL THE WSOC DE-ACCESS USERS WITHOUT NOTIFICATION TO THE WBWO AND THE APPROPRIATE RSSC. 14. CCH If the source of the EMI cannot be determined or resolved, coordinate with the WBWO for further guidance/actions Directs crew(s) to perform EMI mitigation activities IAW WBWO guidance If guidance from higher is to repeat initial assessment, proceed to step 2

Question 33

What is the process for dealing with an downlink EMI after ruling out any other potential reasons for the interference?

Answer 33

1. TC Assist the terminal with troubleshooting the local EMI, as requested 2. TC If maintenance is being performed at the terminal, coordinate for the maintenance equipment to be turned off and see if the EMI goes away 3. TC Coordinate with the TCF or Frequency Manager to determine if the EMI frequency matches a microwave link 4. TC Check the local surrounding area for possible sources of EMI 5. TC Direct the user to submit a JSIR report, if unable to resolve the EMI 6. CCH If the EMI is local to the WSOC, proceed. Otherwise, skip to step 5 7. CCH If the above processes do not isolate the EMI, the CCH will obtain perms from CWO to have terminals (After second roll call) raise total power out Raising terminal total power out (TPO) effects all signals emitted by the terminal. 8. CCH If raising total power out does not work, notify the WBWO to request further assistance in isolating the EMI ***The purpose of having terminals raise their TPO is to see if the EMI raises in power. If the EMI raises in power (roughly) the same amount as the power raise of a given terminal, it is highly likely that terminal is emitting the EMI signal.

Question 34

What is the process for EMI reporting?

Answer 34

1. CCH Submit a Quicklook report IAW Wideband Directives 2. CCH Coordinate with the TC to submit a JSIR report IAW Wideband Directives 3. CCH Update the Quicklook and JSIR reports as new information becomes available or changes 4. CCH Report termination of EMI signals to the WBWO appropriate RSSC, and alternate WSOCs 5. CCH Close the Quicklook report, as required 6. TC Log all actions in the MSL, to include Start and Stop times and actions directed from the WBWO or other agencies

Question 35

In the Uplink EMI section, it was mentioned to clear in-house WSOC equipment to ensure the EMI is not being transmitted from the WSOC. What procedure can be reference to check if the signal is potentially being emitted from the WSOC?

Answer 35

WCG procedure 8.25 Check Site Composite Output a the RRFIS

Question 36

What is a control handover?

Answer 36

When a non-primary WSOC assumes primary control responsibilities from the WSOC that is currently primary on that mission.

Question 37

WSOCs that hold primary control responsibilities are responsible for the following:

Answer 37

* Interface with payload users * Advise the WBWO of any payload or platform issues * Conduct day-to-day satellite activities * Monitor satellite telemetry * Ensure control subsystem databases remain up-to-date with the most current operational database * Maintain situational awareness of the health and welfare of the space, control, and terminal segments

Question 38

WSOCS that hold ALTERNATE control responsibilities are responsible for the following:

Answer 38

BPT (Be Prepared To) assume primary control responsibilities IAW 5.1.8.1 as directed

Question 39

What are some reasons to conduct a handover?

Answer 39

Scheduled handover * Monthly, upcoming exercise Subsystem equipment failure * GSCCE (PC), WRMS(TC), RSCCE(PC) Emergency situation * Fire, Bomb threat, Typhoon Monitoring Terminal HAZCON/ASI Loss of Commercial Power

Question 40

What are the responsibilities of a TC during a control transfer/handover?

Answer 40

1- TC Confirm approval for handover from the CCH 2- TC Verify the configuration (RF connectivity and current databases) of all applicable subsystems in preparation of the handover 3- TC Notify the CCH of subsystem status (ready for handover, or of any required changes) 4- TC In coordination with the CCH, perform procedure 5.7.1 RRFIS Configuration Changes, as required 5- TC Provide the assuming TC an enterprise transmissions summary, including current status, ongoing issues, and upcoming ASIs 6- TC Coordinate between the WSOC TCs to notify all users (Enterprise, Mobile, C4I), as required 7- TC The assuming TC will notify the relinquishing TC when they have accepted the control handover 8- TC Once the assuming TC has accepted the control handover, notify the CCH 9- TC Begin analysis of transmissions performance by scanning WRMS for alarms 10- TC Notify the CCH of a handover summary; including any issues encountered and time control was assumed, so that the CCH can notify the WBWO (Wideband Watch Office) of handover completion 11- TC Log the actions taken, time occurred, and initials of all agencies authorizing the control handover