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GOES-R Direct Readout Implications Richard G. Reynolds GOES-R Ground Segment Project. 4 th GOES User Conference “Session 5: GOES-R User Readiness” 8:30-10:15 am / Wednesday November 4 . An update of the presentation to the Direct Readout Users Conference
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GOES-R Direct Readout ImplicationsRichard G. ReynoldsGOES-R Ground Segment Project 4th GOES User Conference “Session 5: GOES-R User Readiness” 8:30-10:15 am / Wednesday November 4 An update of the presentation to the Direct Readout Users Conference By Wilfred E. Mazur Jr. - December 11, 2008
Topics • Direct Readout Services • GOES-R Program Status • New Instruments for GOES-R • GOES-R Frequency Plan • Implications to Communications Services • GRB and Dual Polarization • GRB Receive Systems • EMWIN & LRIT Become HRIT/EMWIN • Emulated GVAR (eGVAR) • DCS • SARSAT • Multi-Use Data Link (MDL)
Direct Readout Services Overview GOES Rebroadcast (GRB) Emulated GOES Variable (eGVAR) High Rate Information Transmission / Emergency Managers Weather Information Network (HRIT/EMWIN) Data Collection System (DCS) Search and Rescue Satellite Aided Tracking (SARSAT)
GOES-R Program Status Instrument Contracts – ABI / SUVI / EXIS / SEISS / GLM All Under Contract Spacecraft Contract July 22. 2009 – Lockheed-Martin Denver, Colorado NNG07193033J, NNG08193033R / http://prod.nais.nasa.gov/cgi-bin/eps/bizops.cgi?gr=D&pin=51 Ground Segment Contract May 27, 2009 – Harris Corporation Melbourne, Florida DG133E-08-RP-0068 http://www.fedbizopps.gov Antenna System Acquisition October 22, 2009 – Proposals Received GOES-R Access Subsystem (GAS) / Ancillary Data Relay System (ADRS) / HRIT/EMWIN “Domain-5” Upgrade / Data Collection System IF Compatibility Soon – RFP Release GOES-R Launch Readiness Date GOES-S Launch Readiness Date September 2015 -- February 2017
GOES-West 137° West GOES-East 75° West Data Command & control, data Data Direct Readout Users Command & control, data Remote Backup Facility Fairmont, WV NOAA Satellite Operations Facility Suitland, MD Command and Data Acquisition Station Wallops, VA GOES-R System Configuration 06/19/2008 v2 5
GOES-R Frequency Plan DOWNLINKS (RAW DATA DOWNLINK AT 8220 MHz NOT SHOWN) HRIT/EMWIN BPSK 1697.4 MHz DCPC CDMA 468.775 MHz 468.825 MHz DCPR FDM 1683.3 MHz 1683.6 MHz CDA Telemetry BPSK 1696.3 MHz DSN Telem & Rng BPSK/PM 2211.04 MHz SAR FDM 1544.550 MHz GRB (dual pol) 1690.0 MHz Radiosondes 1675 to 1683 MHz 470 2210 1670 1675 1680 1685 1690 1695 1700 1545 DCPC CDMA 2032.775 MHz 2032.825 MHz UPLINKS Command BPSK 2034.2 MHz GRB (dual pol) 7220.0 MHz EMWIN-LRIT BPSK 2028.4 MHz DCPR FDM/8PSK 401.9 MHz 402.2 MHz Command and Ranging BPSK 2036.0 MHz SAR FDM/Bi-Φ 406.05 MHz 400 7225 2025 2030 2035 7210 7215 7220 405
GOES[-R] Rebroadcast (GRB) • Provides full resolution products from all instruments • All data will be calibrated and navigated (“Level 1b”) • Except … GLM will be higher level products (“Level 2+”) • “Events,” “Groups,” and “Flashes” • Replaces current GVAR service • 31 Mbps vs. 2.1 Mbps • DRO receive systems specified for same size antennas (G/T of 15.2 dB/K), however with significant changes: • New center frequency 1690.0 MHz vs. 1685.7 MHz • High-level modulation (e.g. QPSK, OQPSK or 8-PSK, TBD) vs. BPSK • Dual polarization – requiring feed changes and dual receiver chain • CCSDS packet formatting • Forward error detection coding (LDPC) to reduce required C/No. • DVB-S2 link characteristics and compatibility under consideration • System specified for 2.5 dB margin
GOES[-R] Rebroadcast (GRB) (Continued) • LHCP to provide subset of imagery (ABI … 0.64, 3.9, 6.185, 7.34, 11.2, 12.3, 13.3 micron channels); • RHCP to provide remaining 9 ABI channels, plus all other instruments
GRB 99.99% Availability Coverage 0.01% Exceedence of 22 dB interference level based on “Initial Bound Equation” determined by the conducted measurements and the ITU-R 0.01% rain rate for given areas in the GOES antenna footprint. Interference Level Interference level could be exceeded in the DARK BLUE area GOES West GOES East Some locations near the equator may experience a reduced, but positive, margin under expected worst case conditions
One Concept for a GRB Small User Receive System Downconverter Data Antenna & Feed & Aggregator Demodulator Filter LNA 90 deg Demodulator RHCP Hybrid Data Handling Filter LNA LHCP Storage Demodulator
Emulated GVAR (eGVAR) • As a contingency capability, and to give users additional time to transition from GVAR to GRB, eGVAR will provide GOES-R Imagery to Users capable of receiving today’s GVAR data stream • Will be broadcast through a GOES I/P Series Satellite • The signal will have the GVAR characteristics: • Same transmit frequency (1685.7 MHz) and power levels • Same GVAR data rate (2.11 Mbps) and format • Five Similar Imager channel wavelengths (Based on ABI channels 0.64, 4.9, 6.19, 11.2, 13.3 µm) • Imagery will be mapped to GOES NOP temporal and spatial resolution • No Sounder data • One full-earth disk every 30-minutes • No Mesoscale data – No “Rapid Scan;” No “Super Rapid Scan”
Emulated GVAR (eGVAR) (Continued) • Not an option for long-term use • Will only be operational based on assessments of end user readiness near the time for GOES-R operations: • Presumes a spare satellite is available • Users must not be lax in preparing for actual GOES-R (i.e., GRB) readiness
eGVAR & GRB Flows GOES-R Satellite GOES-I/P Series Satellite GOES-N/O/P RF GOES-N/O/P SSGS Product Generation GRB Product Gen eGVAR & GRB Legend Instrument Raw Data downlink GRB relay uplink eGVAR relay uplink GRB RF Broadcast eGVAR RF Broadcast Terrestrial/Network Comm eGVAR User GRB User
HRIT/EMWIN • Successor to individual Low Rate Image Transmission broadcast (LRIT) and the Emergency Managers Weather Information Network broadcast (EMWIN) combined onto one carrier. • Frequency change from 1691.0 MHz/1692.7 MHz to 1694.7 MHz • Higher data rate … 921 Kbps) • Provides growth path for both Services to a combined 400 Kbps • LRIT currently 128 Kbps • EMWIN currently: • 9.6 Kbps (GOES 11&12), 19.2 Kbps for GOES 13-15. • Will utilize BPSK modulation w/ convolutional and Reed-Solomon coding • Same as LRIT, but higher data rate • Allows maximum EIRP from satellite due to Power Spectral Density restrictions • EMWIN Users modulation type changes from uncoded FSK (GOES I-M) and from coded OQPSK (GOES-NOP) to coded BPSK at much higher data rate.
HRIT/EMWIN (Continued) • Name change to High Rate Information Transmission (HRIT) required by CGMS categorization of services • Virtual Channel Data Units used to separate HRIT and EMWIN data • CCSCS Virtual channels as used in LRIT today • Prototype “Software Defined Radio” developed and demonstrated: • One hardware/software configuration can receive all current and future EMWIN, LRIT and HIRT/EMWIN signals with NO hardware changes or upgrades (GOES I-S compatible). No user transition necessary. • Technology demonstration to proves low cost, PC-based terminals are possible for all data rates and modulation types • Performance data, Hardware design and software design is available on WWW.GOES-R .GOV • Development performed for GOES-R Program by Aerospace Corp. • Presentation and Demonstrations provided last night
HRIT/EMWIN Ground Data Flow (Per satellite) GOES-R GS IF Modulation Ant./RF Uplink Processor (Domain 5) RF Up/Down HRIT/EMWIN CCSDS TCP/IP IF Switch IF Switch HRIT/EMWIN Uplink & Signal Monitoring WCDAS EMWIN From NWS NSOF Comm Processor (Domain 4) HRIT From ESPC RBU IF Modulation Ant./RF Uplink Processor (Domain 5) RF Up/Down HRIT/EMWIN CCSDS TCP/IP (B/U) HRIT/EMWIN Uplink & Signal Monitoring GOES-R GS
GOES Data Collection System GOES Data Collection System
GOES Data Collection System • GOES-DCS consists of two communication Services: • Data Collection Platform Receive (DCPR) • Data Collection Command (DCPC) … Previously “Interrogate”(DCPI) • GOES-R will support the ongoing evolution toward greater channel efficiency and system capacity • Narrower DCPR channel assignments allowing both East and West satellites to each support 200 simultaneous platform signals, with a total system capacity of about 72,000 platforms • A new DCPC service, based on CDMA techniques, currently in prototype development. This user-funded development concept will allow one command channel on each GOES NOP Series satellite and two channels on each GOES-R Series satellite • Direct Broadcast of DCPR to User systems having 15.0 G/T will continue to be supported, but ….
GOES Data Collection System (Continued) • Summary of Changes to GOES-DCS for GOES-R Series: • DCP uplink transmit power reduced, in accordance with latest DCP Certification Specifications • DCPR uplink frequencies will be unchanged • DCPR Downlink frequencies will be shifted from 1694.5-1694.8 MHz to 1683.3-1683.6 MHz • Will require change in channel demodulator frequency • DCPI becomes DCPC: • Will be compatible with on-going User-funded developments compatible with current satellites • Able to support a second DCPC channel
SARSAT • Signal characteristics of the SARSAT service will be slightly modified for GOES-R: • Up and down-link center frequencies remain the same • GOES-R will transpond, rather than re-modulate, the up-link band • Will require configuration changes to the LUT receiver • To account for degraded Beacons, GOES-R will operate with 32 dBm uplink power (versus 36 dBm for GOES-NOP) • Provides improved capability to support beacons with weak signals • Transponder will also operate with a minimum of 10 uplink beacons simultaneously • Conforms to COSPAS/SARSAT Specification T001, Issue 3 Revision 8 dated Nov 2007
Other Changes of Potential Interest • All raw instrument data will be transmitted to the ground in X-Band vs. today’s S-Band • X-band provides ‘spot beam’ geographical coverage vs. hemispheric • Processed to Level 1B and re-broadcast to users via the GRB link • Diagnostic telemetry will be available via a new higher data rate telemetry link (32 Kbps) • “CDA” telemetry downlink changes from 1694.0 MHz to 1696.3 MHz • The Multi-use Data Link (MDL) is eliminated for GOES-R Series
Summary • System requirements, communications requirements, and the Ground Segment architecture have been defined for the entire system, including Direct Readout Services • Detailed definition of communication link characteristics have not yet been fully finalized and will be refined through the Spacecraft and Ground Segment contract design processes … However the GOES-R baseline is: • GRB will replace all current forms of instrument data broadcast: • Full resolution • Geo-located • Calibrated • In essentially real-time • EMWIN and LRIT will be combined and enhanced to a higher data rate on a new downlink frequency – HRIT/EMWIN • DCS will remain largely the same, however DCPR downlink in L-Band will have a frequency shift • SARSAT will be essentially unchanged
Summary (Continued) • Documentation for the Direct Readout User community will be produced by the GOES-R Ground System contractor as CDRLs. • Of particular note, the GS Contractor (Harris Corporation) will be developing a Product User's Guide (PUG) that will include a section on building a GRB receive system
GOES N/O/P Frequency Plan DOWNLINKS EMWIN QPSK 1692.7 MHz Radiosondes use 1675 to 1683 MHz CDA Telem Bi-Φ 1694.0 MHz LRIT BPSK 1691.0 MHz DCPI BPSK 468.825 MHz and ± 12.5 kHz DSN Telem BPSK/PM 2209.086 MHz PDR BPSK 1685.7 MHz SAR FDM 1544.550 MHz SD UQPSK 1676.0 MHz MDL QPSK 1681.478 MHz DCPR FDM/8PSK 1694.5 MHz 1694.8 MHz 470 1545 1670 1675 1680 1685 1690 1695 1700 2210 EMWIN QPSK 2034.7 MHz UPLINKS Command BPSK 2034.2 MHz DCPI BPSK 2034.8875 MHz 2034.9000 MHz 2034.9125 MHz PDR 2.11 Mbps 2027.7 MHz DCPR FDM/8PSK 401.9 MHz 402.2 MHz LRIT BPSK 2033.0 MHz SAR FDM/Bi-Φ 406.05 MHz 406.025 MHz 400 2025 2030 2035 405