I P t e l e p h o n ys o l u t i o n s

Codan L-Band Block Upconverter (BUC) System

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Codan L-Band Low Power Block Upconverter (LBUC) -Codan L-Band Low Power Block Upconverter (LBUC) -

Technical Overview

Main Components

Low Power BUC(Block Upconverter)

TRANSMIT

LNB

RECEIVE

Low Power Block Upconverter (LBUC)Low Power Block Upconverter (LBUC)

BUC(Block Up Converter)

TX L-Band Input10 MHz Freq Ref from Comtech ModemFSK M&C to and from Comtech Modem

24 or 48 VDC from modem

RX L-Band Output from LNB+15VDC power from Comtech modem

+10MHz Freq Ref from Comtech modedmLNB

Antenna

Transceiver Block Diagram

L-Band IF Transceiver - TransmitL-Band IF Transceiver - Transmit

• Tx IF cable carries:

Tx L-Band IF signal Frequency Reference from Modem or Interface Unit (10 MHz)

FSK Monitor & Control signals

24 or 48VDC for LBUC supplies

L-Band IF Transceiver - ReceiveL-Band IF Transceiver - Receive

• LNBOptional from Codan

C-Band & Ku-Band versions

Rx IF cable carries:Rx IF signal from LNB to the ModemPower from Modem (15 VDC nominal)Reference Frequency from Modem (10 MHz)

LNB SpecificationsLNB Specifications

• Frequency range

• Ku-Band Band 1 10.95 - 11.70 GHz Band 2 11.70 - 12.20 GHz

Band 3 12.25 - 12.75 GHz

• Gain• Ku-Band 60 dB

• Noise temperature• Ku-Band 75 K max

Block Upconverter (BUC) Transmit Frequency ConversionsBlock Upconverter (BUC) Transmit Frequency Conversions

• The Block Upconverter (BUC) is responsible for the transmission of the desired carrier at the correct TX frequency. It takes the L-Band input from the modem and upconverts it to Ku-Band.

• The BUC is a single conversion system which is frequency inverting. Therefore, the higher the L-Band frequency the lower the transmit RF frequency.

• Ku-Band does not require the LO set - only one LO frequency is required to cover the full Ku-Band frequency plan. This LO Frequency is 15.450 GHz

• To calculate the required modem IF frequency for a given RF frequency:•

frequencyIF = frequencyLO – frequencyRF

BUC Frequency Plan (Ku-Band)BUC Frequency Plan (Ku-Band)

• Ku-Band - LBUC• RF: 13750 - 14500 MHz• IF: 950 - 1700 MHz• LO fixed at 15450 MHz

Ku-Band - MBUCRF: 14000 - 14500 MHz

IF: 950 - 1450 MHzLO fixed at 15450 MHz

1700 MHz

1450 MHz

950 MHz

14500 MHz

14000 MHz

13750 MHzIF input RF output

1450 MHz

950 MHz 14000 MHz

14500 MHz

IF input RF output

Low Noise Block Downconverter (LNB) Frequency PlanLow Noise Block Downconverter (LNB) Frequency Plan

• Each Low Noise Block Downconverter (LNB) used in this system has its own internal Reference Oscillator it uses to downconvert the received Ku-Band Signals to L-Band signals. This oscillator is commonly referred to as the Local Oscillator (LO). The LO frequency is different depending on the 3 different Receive Bands.

• The three Receive Bands are:Band 1 10.95 - 11.70 GHz LNB LO Freq = 10.00 GHzBand 2 11.70 - 12.20 GHz LNB LO Freq = 10.75 GHz Band 3 12.25 - 12.75 GHz LNB LO Freq = 11.30 GHz

• The LNB Downconversion process is a single step process that is NOT Frequency Inverted. This means that the LO frequency is subtracted from the Ku-Band Receive frequency to determine the L-Band Receive Frequency.

frequencyIF = frequencyRF – frequencyLO

Frequency Conversion Examples - TransmitFrequency Conversion Examples - Transmit

• Following are frequency conversion calculation examples based on the R/V Oceanus Shipboard configuration.

Transmit Frequency - Calculate the L-Band transmit frequency to be entered in the Comtech modem to transmit the correct Ku-Band frequency.

Required Transmit Ku-Band Frequency => 14.436215 GHz (14436.215 MHz)BUC LO Frequency => 15.450 GHz (15450 MHz)

frequencyIF = frequencyLO – frequencyRF

frequencyIF = 15450 MHz – 14436.215 MHz

frequencyIF = 1013.785 MHz

Frequency Conversion Examples - ReceiveFrequency Conversion Examples - Receive

Following are frequency conversion calculation examples based on the R/V Oceanus Shipboard configuration.

Receive Frequency - Calculate the L-Band receive frequency to be entered in the Comtech modem to receive the transmitted Ku-Band frequency.

First – Convert the Transmit Ku-band frequency to the Receive Ku-Band frequency. Do this by subtracting the satellite translation value from the TX Ku-Band frequency. The satellite translation value is 2300 MHz

Transmit Ku-Band Frequency - Translation = Receive Ku-Band Frequency14436.215 MHz - 2300 MHz = 12136.215 MHz

Next – Subtract the LNB LO frequency from the Receive Ku-Band Frequency to determine the correct Receive L-Band Frequency

frequencyIF = frequencyRF – frequencyLO

frequencyIF = 12136.215 MHz - 10750 MHz frequencyIF = 1386.215 MHz

BUC Indicators/AlarmsBUC Indicators/Alarms

• There are three LEDs on the BUC

• PWR (Power) Green – Indicating Power present

• Tx (Transmit) Yellow – Indicates BUC RF PA is ON

• FLT (Fault) Red – Two possible states:On – steadyFlash – two flashes every

second

BUC Fault LEDBUC Fault LED

• OFF No Faults or latched faults present.

• ON Fault Condition exists• Over Temperature (>90ºC)• Fan Fault• PA Fault• LO Fault• Output power below set threshold• Hardware/software incompatibility

• Flashing Primarily used in Redundant Systems to indicate:* LNB Fault* Redundancy Controller Fault

(NOTE HiSeasNet does not have any redundant systems)

Codan L-Band LBUCCodan L-Band LBUC• BUC Command List – 69xx

• HLP• General Help (this Display) HLP• Help for Set Commands HSC• Help for Output Commands HOC• Help for Reset Commands HRC• Help for View Commands HVC

• HSC• Set Transmit On STOn n=0: Off, n=1: On• Set On Line SOLn n=0: Off-Line, n=1: On-Line• Set Compensation Freq SCFn 13750<=n<=14500, 950<=n<=1700, n=0: Wideband• Set Transmit Attenuator STAn n=0, 4, 8, 12• Set Tx Alarm Threshold SATn 16.0<=n<=33.0, n=0: Disable• Set Burst Threshold SBTn 16.0<=n<=33.0, n=0: Disable• Set LO Frequency SLOn n=15450• Set Transmit Default STDn n=0: Transmit Off, n=1: Last State• Set Redundancy Mode SRMn n=0: Non, n=1: Warm, n=2: Hot• Set Serial Interface SSIr,l,p,s,t (Rate, Len, Parity, Stop, Term)• Set Packet Protocol SPPn 0<=n<=4• Set Packet Address SADn 1<=n<=126• Set Echo SECn n=0: Echo Off, n=1: Echo On

Codan L-Band LBUCCodan L-Band LBUC• BUC Command List – 69xx (cont)

• HOC

• Output Tx On OTO Output On Line State OOL• Output Tx Frequency OCF Output Tx Attenuator OTA• Output Pwr Alarm Thresh OAT Output Burst Threshold OBT• Output LO Frequency OLO Output Tx Default OTD• Output Redundant Mode ORM Output Serial I/face OSI• Output Packet Protocol OPP Output Packet Address OAD• Output Echo OEC Output System Status OSS• Output Fault Status OFS Output Latched Faults OLF• Output Status Poll OSP Output PA State OPA• Output Burst Power OBP Output Power Output OPO• Output Temp of BUC OTB Output IF Compen. Freq OIC• Output Identity Data OID Output Max/Min Temps OMT• Output Protocol Data OPD Output Limit Data OLD• Output Device Type ODT Output Build Standard OBS• Output BUC Config OBC

Codan L-Band LBUCCodan L-Band LBUC

• BUC Command List – 69xx (cont)

• HRC

• Reset BUC RST Reset Change Bits RCB• Reset to Default Values RDV Reset Latched Faults RLFHVC• View System Status VSS View Fault Status VFS• View Limit Data VLD View Protocol Data VPD• View Operational Data VOD View Build Standard VBS• View Identity Data VID