CDM-625A Advanced Satellite Modem
Satellite Modems

Typical Users

Overview
The CDM-625A Advanced Satellite Modem builds on our legacy of providing®
the most efficient satellite modems. With support for VersaFEC Forward
Error Correction (FEC), the revolutionary DoubleTalk Carrier-in-Carrier
bandwidth compression, additional rolloffs and advanced packet processing,
the CDM-625A provides significant savings under all conditions. This
combination of advanced technologies enables multi-dimensional
optimization, allowing satellite communications users to:• Minimize operating expenses (OPEX)• Maximize throughput without using additional transponder resources• Maximize availability (margin) without using additional transponder
resources• Minimize capital expenses (CAPEX) by allowing a smaller BUC/HPA
and/or antenna• Or, a combination to meet specific business needs• Mobile Network Operators• Telecom Operators• Satellite Service Providers• Government & Military• Enterprise• Offshore
Common Applications• Mobile Backhaul• G.703 Trunking• IP Trunking• Offshore & Maritime Communications• Enterprise• Communications on-the-Move• Satellite News Gathering

Features• DoubleTalk Carrier-in-Carrier bandwidth compression• Carrier-in-Carrier Automatic Power Control• VersaFEC FEC with Adaptive Coding and Modulation (ACM)• 5%, 10%, 15%, 20%, 25% and 35% Filter Rolloff• Packet Processor with header compression, payload
compression, advanced Quality of Service (QoS) andManaged Switch Mode with VLAN support• Integrated 4-port managed Ethernet switch with VLAN and QoS• Jumbo frame support• Dual Band Capability: 70/140 MHz and extended L-Band(950 – 2250 MHz) in same unit
• Data Rate: 18 kbps to 25 Mbps
• Symbol Rate: 18 ksps to 12.5 Msps
• Modulation: BPSK, QPSK/OQPSK, 8PSK/8-QAM, 16-QAM• FEC: Viterbi, Sequential, Concatenated Reed Solomon, TCM,
Turbo Product Code (TPC) (IESS-315 Compliant), LDPC Codeand VersaFEC (low-latency LDPC)• Widest Range of data interfaces: EIA-422/530, V.35, G.703 T1,
G.703 E1, G.703 T2, G.703 E2, Quad G.703 E1, ASI, LVDS,HSSI, 4-port 10/100Base-T Ethernet• IEEE 1588v2 Precision Time Protocol• Sub Mux to multiplex IP/Ethernet traffic with serial or G.703
traffic• Drop & insert for T1/E1• Enhanced D&I++ for single T1/E1 & quad E1• Management: 10/100Base-T Ethernet with SNMP, Distant
End SNMP Proxy, HTTP, Telnet and EIA-232/EIA-485®
• Carrier ID using MetaCarrier Technology• Embedded Distant-end Monitor and Control (EDMAC)• Automatic Uplink Power Control (AUPC)• Engineering Service Channel (ESC/ESC++)• Standard high-stability internal reference-8(± 6 x 10 )• 5-tap Adaptive Equalizer• L-Band TX: 10 MHz reference for BUC, FSK communications
and optional BUC power supply• L-Band RX: 10 MHz reference and LNB power supply• L-Band: Advanced FSK for LPOD M&C• 1:1 and 1:10 redundancy switches available• Backwards compatible with CDM-625

Doubletalk Carrier-in-Carrier
DoubleTalk Carrier-in-Carrier, based on patented “Adaptive Cancellation” technology, allows transmit and receive carriers of a duplex
link to share the same transponder bandwidth. DoubleTalk Carrier-in-Carrier is complementary to all advances in modem technology,
including advanced FEC and modulation techniques. As these technologies approach theoretical limits of power and bandwidth
efficiencies, DoubleTalk Carrier-in-Carrier utilizing advanced signal processing techniques provides a new dimension in bandwidth
efficiency.

www.comtechefdata.com

Figure 1 shows the typical full-duplex satellite link, where the two carriers are adjacent to each other.
Figure 2 shows the typical DoubleTalk Carrier-in-Carrier operation, where the two carriers are overlapping, thus sharing the same
spectrum.

Figure 2

Figure 1

When observed on a spectrum analyzer, only the Composite is visible. Carrier 1 and Carrier 2 are shown in Figure 2 for reference only.
As DoubleTalk Carrier-in-Carrier allows equivalent spectral efficiency using a lower order modulation and/or code rate, it can reduce thepower required to close the link thereby reducing CAPEX by allowing a smaller BUC/HPA and/or antenna. Alternatively, DoubleTalk
Carrier-in-Carrier can be used to achieve very high spectral efficiencies E.g., DoubleTalk Carrier-in-Carrier when used with 16-QAM
approaches the bandwidth efficiency of 256-QAM (8 bps/Hz).
When combined with VersaFEC or LDPC/TPC, it can provide unprecedented savings in transponder bandwidth and power utilization.
This allows for its successful deployment in bandwidth-limited and power-limited scenarios, as well as reduction in earth station
BUC/HPA power requirements.
Carrier-in-Carrier® is a Registered Trademark of Comtech EF Data
DoubleTalk® is a Registered Trademark of Raytheon Applied Signal Technology
VersaFEC is a Registered Trademark of Comtech EF Data

Carrier-in-Carrier Automatic Power Control (CnC-APC)
The patent-pending Carrier-in-Carrier Automatic Power Control (CnC-APC) mechanism enables modems on both sides of a CnC link toautomatically measure and compensate for rain fade while maintaining the Total Composite Power. In addition to automaticallycompensating for rain fade, CnC-APC also enables the modems to share link margin, i.e. a modem in clear sky conditions caneffectively transfer excess link margin to a distant end modem experiencing fade, thereby further enhancing overall availability.

VersaFEC Forward Error Correction
CDM-625A offers VersaFEC, a patent-pending system of high-performance LDPC codes designed to provide maximum coding gain
while minimizing latency. VersaFEC is designed to support ACM and CCM mode of operation
The Ultra Low Latency (ULL) codes provide even lower latency compared to standard VersaFEC codes.

Adaptive Coding & Modulation (ACM)
Satellite users have traditionally relied on worst case link margin to overcome rain fade which leads to significant inefficiencies. ACM
can provide significant increase in throughput as well as availability. ACM converts the fade margin into increased capacity making it
possible to more than double the throughput for Ku-band operation. Even under deep fade, ACM may be able to maintain the link at thelower MODCOD thereby increasing availability. It is tightly integrated with packet processor QoS which allows higher priority, mission
critical traffic to be maintained even during fade.

Low Density Parity Check Codes (LDPC) & Turbo Product Codes (TPC)nd

CDM-625A offers an integrated LDPC and 2 Generation TPC codec. LDPC is an advanced Forward Error Correction techniquecapable of providing performance much closer to Shannon limit. The current LDPC implementation can provide 0.7 to 1.2 dB additional
coding gain compared to an equivalent TPC code.
In order to take full advantage of the increased coding gain provided by LDPC, Comtech EF Data has developed a patented 8-QAM
modulation that allows for acquisition and tracking at much lower Eb/No compared to 8PSK.

Dual Band Capability
CDM-625A supports 70/140 MHz and extended L-Band (950 – 2250 MHz) capability in the same unit with independently selectabletransmit and receive IF. This simplifies sparing and stocking in networks requiring 70/140 MHz and L-Band units.

4-Port Managed Ethernet Switch with VLAN & QoS
CDM-625A incorporates a 4-port 10/100Base-T managed Ethernet switch with VLAN capability and priority-based Quality of Service.
Access (Native) Mode and Trunk Mode are supported. Traffic can be prioritized using port-based priority or VLAN priority. The modem
supports jumbo frames with maximum Ethernet frame size of 2048 bytes.

Packet Processor
The optional high-performance Packet Processor enables efficient IP networking and transport over satellite with low overhead
encapsulation, header compression, payload compression and advance Quality of Service to the CDM-625A. The QoS combined withheader and payload compression ensures the highest quality of service with minimal jitter and latency for real-time traffic, priority
treatment of mission critical applications and maximum bandwidth efficiency.
Packet processor supports Routed mode as well as Managed Switch Mode of operation. In managed switch mode, it operates as alayer 2 switch with VLAN support, enabling seamless integration with existing infrastructure while providing full optimization including
low overhead Streamline Encapsulation, header compression and payload compression and advanced QoS.
Header Compression
The Packet Processor incorporates industry-leading header compression for Ethernet and IP traffic. In managed switch mode, header
compression can reduce the 54 byte Ethernet/IP/UDP/RTP header to as little as 1 byte. For TCP/IP, the 54 byte header (including
Ethernet) is reduced to as little as 3 bytes. For applications such as VoIP, header compression can provide bandwidth savings
exceeding 65%. E.g. the 8 kbps G.729 voice codec requires 31.2 kbps once encapsulated into an Ethernet frame with IP/UDP/RTP.
With header compression, the same voice call needs about 9 kbps – a saving of almost 70%. And, bandwidth requirements for typical
Web/HTTP traffic can be reduced by 10% or more with TCP/IP header compression.
Payload Compression
The Packet Processor incorporates industry-leading GZIP based payload compression for IP/Ethernet traffic. Implemented in hardware
for maximum throughput and efficiency, payload compression can typically reduce the required satellite bandwidth by 30-40%.
Streamline Encapsulation (SLE)The Packet Processor incorporates Comtech EF Data’s patent-pending low overhead Streamline Encapsulation (SLE). SLE can reduce
the encapsulation overhead by as much as 65% compared to industry standard HDLC.
Advanced Quality of Service (QoS)
The Packet Processor incorporates multi-level QoS to ensure the highest quality service with minimal jitter and latency for real-timetraffic, priority treatment of mission critical applications and maximum bandwidth efficiency. Supported modes are:• DiffServ – Industry-standard method of providing QoS enabling seamless co-existence in networks that implement DiffServ• Max/Priority – Provides traffic prioritization with the ability to limit maximum traffic per priority class• Min/Max – Provides a Committed Information Rate (CIR) to each user defined class of traffic with the ability to allow a higher
burstable rate depending on availability
A powerful classifier supports packet classification by Protocol, VLAN ID / range, ToS Byte, Source IP (or subnet), Destination IP (orsubnet), Source Port (or Range), Destination Port (or Range) and DSCP (for DiffServ).

Quad E1 Interface (QDI) with Enhanced D&I++
The CDM-625A supports a Quad E1 interface that can aggregate up to four full or fractional E1s into a single carrier, with very low
overhead. This provides significant CAPEX savings by reducing the number of modems and could possibly reduce the BUC/HPA sizeby eliminating the multi-carrier backoff. A proprietary, closed network drop & insert (D&I++) allows for dropping or inserting any
combination of 1 to 31 time slots on each E1. D&I++ is supported for E1-CCS only.

IP Sub Multiplexer
The IP sub mux allows multiplexing IP/Ethernet traffic with serial or G.703 traffic into a single carrier. This is particularly useful forcellular backhaul when both E1 and IP backhaul is required. This reduces the number of modems and could possibly reduce the
BUC/HPA size by eliminating the multi-carrier backoff. The IP sub mux ratio ranges from 9:1 (IP data rate is 9 times that of the serial or
G.703 data rate) to as low as 1:59. IP sub mux can also be used to provision an overhead IP channel for management when using non
IP/Ethernet traffic interfaces.

EDMAC & AUPCThe CDM-625A supports EDMAC, EDMAC-2, EDMAC-3 and AUPC. EDMAC/EDMAC-2/EDMAC-3 can be used to monitor and control
the distant end of a satellite link using a proprietary overhead channel. EDMAC-3 is also used for SNMP management of the distantend modem. AUPC automatically adjusts modem transmit power based on feedback from the distant end modem to maintain thedesired Eb/No. AUPC and EDMAC are supported for point-to-point duplex links.

Management & SNMP Proxy
The modem can be managed via the front panel, the remote M&C port (EIA-232/EIA-485), or the 10/100Base-T Ethernet port. With
support for SNMP, HTTP and Telnet, the modem can be easily integrated into an IP-based management system.
The CDM-625A can also act as SNMP proxy for the distant end CDM-625A. This allows distant end CDM-625A management using
SNMP without requiring an end-to-end IP link.

IEEE 1588v2 Precision Time Protocol (PTP)
PTP has emerged as the key technology for frequency, time and phase synchronization over a packet network. The CDM-625A
incorporates hardware support for PTP, thereby significantly improving synchronization accuracy for satellite backhaul.

Advanced FSK for LPOD Monitoring & Control
The Advanced FSK allows for monitoring and control of LPOD through modem front panel menus, serial remote control and Telnet.

Feature Enhancements
Enhancing the capability of the CDM-625A in the field is easy. Features that do not require additional hardware can be added on site,using FAST access codes purchased from Comtech EF Data.

Specifications
Data Rate
Symbol Rate
Operating
Frequency
Major Operating
Modes(See User Manual
For Details)

FEC & Modulation
None
Viterbi: k=7, per
IESS-308/309
Viterbi with Reed
SolomonSequential
Reed Solomon
TCM (Per IESS310)
Integrated LDPC
ndand TPC (2 Gen)
Codec (Optional
Plug-in Module)

VersaFEC Codec(Option)

Scrambling

Management
Form C Relays
External Reference(Input OR Output)

18 kbps to 25 Mbps, in 1 bps steps(modulation, FEC & data interface dependant)
18 ksps to 12.5 Msps
50 – 180 MHz (standard) and
950 – 2250 MHz (option)
100 Hz resolution, independent TX and RX operation
Open network, per IESS-308 / 309 / 310 / 314
transparent, closed network per IESS-315
LDPC / TPC Codec (option)
VersaFEC Codec (option) with ACM or Constant Coding &Modulation (CCM)
EDMAC Framed with/without AUPC
RS Outer Codec
High rate ESC / Enhanced ESC (ESC++)
Drop & insert (D&I) /Enhanced D&I++ (option)
Quad E1 drop & insert (QDI) (option)
DoubleTalk Carrier-in-Carrier (option)
Uncoded BPSK/QPSK/OQPSK
Rate 1/2 BPSK/QPSK/OQPSK
Rate 3/4 QPSK/OQPSK
Rate 7/8 QPSK/OQPSK
Rate 3/4 16-QAM
Rate 7/8 16-QAM
See CDM-625A user manual for details
Open network and closed network modes
8PSK/TCM Rate 2/3
LDPC Code Rates
Rate 1/2 BPSK/QPSK/OQPSK
Rate 2/3 QPSK/OQPSK/8PSK/8-QAM
Rate 3/4 QPSK/OQPSK/8PSK/8-QAM/16-QAM
TPC Code Rates
Rate 5/16 BPSK
Rate 21/44 BPSK/QPSK/OQPSK
Rate 3/4 QPSK/OQPSK/8PSK/8-QAM/16-QAM
Rate 7/8 QPSK/OQPSK/8PSK/8-QAM/16-QAM
Rate 0.95 QPSK/OQPSK/8PSK/8-QAM
BPSK Rate 0.488
QPSK Rate 0.533, 0.631, 0.706, 0.803
8-QAM Rate 0.576 (ECCM), 0.642, 0.711, 0.780
16-QAM Rate 0.644 (ECCM), 0.731, 0.780, 0.829, 0.853
BPSK 0.493 (ULL)QPSK 0.493, 0.654, 0.734 (ULL)IDR Mode, no RS, - per ITU V.35 (Intelsat variant)
IBS mode, no RS - per IESS-309, externally frame
synchronizedTransparent Closed Network mode, no RS or Turbo coding per ITU V.35 (Intelsat variant)
EDMAC mode, no RS coding - externally frame
synchronized - proprietary
Turbo Product Code/LDPC/VersaFEC modes - externally
frame synchronized - proprietary
All RS modes - externally frame synchronized per IESS308/309/310
10/100Base-T Ethernet with SNMP, HTTP and Telnet
support, EIA-232, EIA-485 (2- or 4-wire)
Hardware fault, RX and TX traffic alarms, open network
backward alarms
BNC connector
Input: 1, 2, 5, or 10 MHz, -6 dBm to+10 dBm, 50 Ω/75 Ω (nominal)
Output: 10 MHz, 2.7 V peak-to-peak± 0.4 V, low impedance output

Data Interfaces
EIA-422/-530 DCE , Up to 14 Mbps
V.35 DCE , Up to 14 Mbps
LVDS Serial , Up to 25 Mbps
HSSI Serial , Up to 25 Mbps
G.703 T1, 1.544 Mbps
(Balanced 100 Ω)
G.703 T2, 6.312 Mbps
(Unbalanced 75 Ω or balanced
110 Ω)
G.703 E1, 2.048 Mbps
(Unbalanced 75 Ω or balanced
120 Ω)
G.703 E2, 8.448 Mbps (Unbalanced 75 Ω)
ASI , Up to 25 Mbps
Additional 2.048 Mbps E1 Ports for QuadE1 (Balanced 120 Ω)Overhead Data
Modem Alarms
4-port 10/100Base-T Managed Ethernet
Switch(Optional Packet Processor Available)

Modulator
Frequency Stability
Transmit Filtering
Alpha (Rolloff)
Harmonics and Spurious

Transmit On/Off Ratio
Output Phase Noise

Output PowerPower Accuracy

Output Impedance &Return Loss

Clocking Options

External TX Carrier Off
BUC Reference(10 MHz)BUC Power Supply(HW Option)

25-pin D-sub (female)
25-pin D-sub (female)

9-pin D-sub (female)or
BNC (female)

BNC (female)
9-pin D-sub (female)
44-pin High-density D-sub (male)
15-pin D-sub (male)
4 x RJ-45± 0.06 ppm (± 6 x 10-8), 0° to 50°C (32° to
122°F) with internal reference
Per IESS-308
5%, 10%, 15%, 20%, 25%, 35%
Better than -60 dBc/4 kHz(typically <-65 dBc/4kHz)
Measured from 1 to 500 MHz(50-180 MHz band)
Measured F0 ± 500 MHz(950-2250 MHz band)-60 dBc minimum< 0.480° rms double sided, 100 Hz to 1 MHz(Minimum 16 dB better overall than the Intelsat IESS308/309 requirements)
dB/Hz
Frequency Offset-63.0
100 Hz
-73.0
1 kHz
-83.0
10 kHz-93.0
100 kHz
Fundamental AC line spurious is -42 dBc or lower
The sum of all other single sideband spurious, from0 to 0.75 x symbol rate, is -48 dBc or lower
50-180 MHz:
0 to -25 dBm, 0.1 dB steps
950-2250 MHz:
0 to -40 dBm, 0.1 dB steps
50-180 MHz:± 0.5 dB over frequency, data rate, modulation type
and temperature range of 15 to 35° C± 0.8 dB over frequency, data rate, modulation type
and temperature range of 0 to 50° C
950-2250 MHz:± 0.7 dB over frequency, data rate, modulation type
and temperature range of 15 to 35° C± 1.0 dB over frequency, data rate, modulation type
and temperature range of 0 to 50° C
50-180 MHz: 50 Ω/75 Ω, 16 dB minimum return loss
(18 dB typical), BNC connector
950-2250 MHz: 50 Ω, 19 dB minimum return loss
(21 dB typical), Type-N connector
Internal, ± 0.06 ppm (SCT)
External, locking over a ± 100 ppm range (TT)Loop timing (RX satellite clock) – supports
asymmetric operation
External clock
By TTL ‘low’ signal or external contact closure
Via TX IF center conductor, 10.0 MHz± 0.06 ppm (with internal reference), selectable
on/off, 0.0 dBm ± 3 dB
24 VDC, 4.17 Amps max., 90 W @ 50° C
48 VDC, 3.125 Amps max., 150 W @ 50° C(180 W @ 30° C)
Supplied through TX IF center conductor andselectable on/off via M&C control

Demodulator
Input Power Range, Desired
Carrier

Max Composite Operating
Level

Absolute Maximum
Adaptive Equalizer
Acquisition Range
Below 64 ksymbols/sec
Between 64 and389 ksymbols/sec
Above 389 ksymbols/sec
Acquisition Time

Plesiochronous/
Doppler Buffer
Receive Clock
Clock Tracking
LNB Reference (10 MHz)LNB Voltage
Monitor Functions

Available Options
50-180 MHz: -105 + 10 log (symbol rate) to-70 + 10 log (symbol rate) dBm
950-2250 MHz: -130 + 10 log (symbol rate) to -80 +10 log (symbol rate) dBm
50-180 MHz:
94 – 10 log (symbol rate, desired carrier) dBc, +10
dBm max., with the additional requirement thatwithin ± 10 MHz of the desired carrier thecomposite power is ≤ +30 dBc
950-2250 MHz:
102 – 10 log (symbol rate, desired carrier) dBc, +10
dBm max., with the additional requirement thatwithin ± 10 MHz of the desired carrier thecomposite power is ≤ +30 dBc+20 dBm
5-tap design, selectable on/off
Programmable in 1kHz increments± 1 kHz to ± (Rs/2) kHz, where Rs = symbol rate in
ksymbols/sec± 1 kHz to ± 32 kHz± 1 kHz to ± (0.1 * Rs) kHz, up to a maximum of ±200 kHz
Highly dependent on data rate, FEC rate, anddemodulator acquisition range.
E.g. 120 ms average at 64 kbps, R1/2 QPSK, ± 10
kHz acquisition sweep range,
6 dB Eb/No
Selectable from 64 to 262,144 bits, in 16-bit steps(Additional limitations for G.704 frame boundaries)
RX satellite, TX terrestrial, external reference± 100 ppm minimum
Via RX IF center conductor, 10.0 MHz± 0.06 ppm (with internal reference), selectable
on/off, -3.0 dBm ± 3 dB
Selectable on/off, 13 VDC, 18 VDC per DiSEq 4.2
and 24 VDC at 500 mA maximum
Eb/N0 estimate, corrected BER, frequency offset,
buffer fill state, receive signal level

DoubleTalk Carrier-in-Carrier
Delay Range
Power Spectral Density
Ratio(Interferer to Desired)
Maximum Symbol Rate
Ratio
Eb/No Degradation

Satellite Restrictions

0 to 330 ms
BSPK/QPSK/8PSK/8-QAM: –7 dB to+11 dB
16-QAM: -7 dB to +7 dB
3:1 (TX:RX or RX:TX)

HardwareHardwareHardwareHardwareHardwareHardwareHardware
FAST
FAST
FAST
FAST
FAST
FAST
FAST
FAST
FAST
FAST
FAST
FAST
FAST
FAST
FAST
FAST
FAST

100 – 240 VAC, 175 W AC primary power supply-48 VDC, 125 W primary power supply-24 VDC, 120 W primary power supply
24 VDC, 90 W @ 50°C BUC power supply, AC, 24 VDC or 48 VDC
primary power supply
48 VDC, 150 W @ 50°C (180 W @ 30°C) BUC power supply, AC or
48 VDC primary power supplyndIntegrated TPC (2 generation) and LDPC Codec module
Packet Processor
L-Band IF (in addition to 70/140 MHz)
Modem data rate – 10 Mbps, 15 Mbps, 20 Mbps or 25 Mbps
8PSK and 8-QAM modulation (8-QAM requires TPC/LDPC or
VersaFEC Codec)
16-QAM modulation
TPC/LDPC Codec data rate – 10 Mbps, 15 Mbps, 20 Mbps or 25
Mbps
Activate DoubleTalk Carrier-in-Carrier Feature
DoubleTalk Carrier-in-Carrier Data Rate (full) – 512 kbps, 1.1 Mbps,
2.5 Mbps, 5 Mbps, 10 Mbps, 15 Mbps, 20 Mbps or 25 Mbps
DoubleTalk Carrier-in-Carrier Data Rate (fractional) – 2.5 Mbps, 5
Mbps, 10 Mbps, 15 Mbps, 20 Mbps or 25 Mbps
VersaFEC Codec data rate (CCM) – 1.1 Mbps, 2.5 Mbps, 5 Mbps or
16 Mbps
VersaFEC Codec symbol rate (ACM) – 300 ksps, 1.2 Msps or
4.1 Msps
Open network – IBS with high rate IBS ESC, IDR and audio
D&I / D&I++ for single Port T1/E1
D&I++ For Quad E1 Port 2, 3 and 4
Quality of Service (requires Packet Processor)
Header Compression (requires Packet Processor)
Payload Compression (requires Packet processor)
Advanced Network Timing (IEEE 1588v2 PTP)

Accessories
CRS-170A
CRS-180
CRS-300
CRS-280
CRS-280L
CRS-500
CRS-282XXX

Environmental and Physical
Temperature

0 dB Power Spectral Density Ratio
BPSK/QPSK/OQPSK: 0.3 dB
8-QAM: 0.4 dB
8PSK: 0.5 dB
16-QAM: 0.6 dB+10 dB power spectral density ratio
Additional 0.3 dB
Satellite in “loop-back” mode (i.e., the transmit
station can receive itself)“Non-processing” satellite (i.e., does notdemodulate or remodulate the signal)

1:1 Modem Redundancy Switch (L-Band)
1:1 Modem Redundancy Switch (70/140 MHz)
1:10 Modem Redundancy Switch(Not available with Packet Processor)
1:10 IF Redundancy Switch (70/140 MHz)
1:10 IF Redundancy Switch (L-Band)
1:N Modem Redundancy System(For use with Packet Processor Only)
1:10 IF Redundancy Switch(For use with CRS-500)

Power Supply

Dimensions (1RU)(height x width x
depth)
Weight
CE Mark

FCC

Operating: 0 to 50°C (32 to 122°F)
Storage: -25 to 85°C (-13 to 185°F)
100 – 240 VAC, +6%/-10%, 50/60 Hz, auto sensing-24 VDC (HW option)-48 VDC (HW option)
1.75” x 19.0” x 17.65”(4.4 x 48 x 44.8 cm) approximate
10.8 lbs (4.9 kg) maximum, with all option modules and
48 VDC BUC power supply installed
EN 301 489-1 (ERM)
EN55022 (Emissions)
EN55024 (Immunity)
EN 61000‐3‐2
EN 61000‐3‐3
EN60950 (Safety)
FCC Part 15, Subpart B

2114 West 7th Street, Tempe, Arizona 85281 USA
Voice: +1.480.333.2200 ● Fax: +1.480.333.2540 ● Email: sales@comtechefdata.com
See all of Comtech EF Data’s Patents and Patents Pending at http://patents.comtechefdata.com
Comtech EF Data reserves the right to change specifications of products described in this document at any time without notice and without obligation to notify any person of such changes. Information inthis document may differ from that published in other Comtech EF Data documents. Refer to the website or contact Customer Service for the latest released product information© 2013 Comtech EF Data
ds-CDM-625A.docx
9/5/2013

CDM-625A-EN Advanced Satellite Modem
Satellite Modems

Typical Users

Overview
The CDM-625A-EN Advanced Satellite Modem builds on our legacy ofproviding the most efficient satellite modems for IP-centric applications that®
require data encryption. With support for VersaFEC Forward Error

Correction (FEC), the revolutionary DoubleTalk Carrier-in-Carrier
bandwidth compression, additional rolloffs and advanced packet processing,
the CDM-625A-EN provides significant savings under all conditions. This
combination of advanced technologies enables multi-dimensional
optimization, allowing satellite communications users to:• Minimize operating expenses (OPEX)• Maximize throughput without using additional transponder resources• Maximize availability (margin) without using additional transponder
resources• Minimize capital expenses (CAPEX) by allowing a smaller BUC/HPA
and/or antenna• Or, a combination to meet specific business needs• Mobile Network Operators• Telecom Operators• Satellite Service Providers• Government & Military• Enterprise• Offshore
Common Applications• Mobile Backhaul• G.703 Trunking• IP Trunking• Offshore & Maritime Communications• Enterprise• Communications on-the-Move• Satellite News Gathering

Features• DoubleTalk Carrier-in-Carrier bandwidth compression• Carrier-in-Carrier Automatic Power Control• VersaFEC FEC with Adaptive Coding and Modulation (ACM)• 5%, 10%, 15%, 20%, 25% and 35% Filter Rolloff• Packet Processor with header compression, payload
compression, advanced Quality of Service (QoS) andManaged Switch Mode with VLAN support• Integrated 4-port managed Ethernet switch with VLAN and QoS• Jumbo frame support• AES Data Encryption for IP traffic (Packet Processor)• Dual Band Capability: 70/140 MHz and extended L-Band(950 – 2250 MHz) in same unit
• Data Rate: 18 kbps to 25 Mbps
• Symbol Rate: 18 ksps to 12.5 Msps
• Modulation: BPSK, QPSK/OQPSK, 8PSK/8-QAM, 16-QAM• FEC: Viterbi, Sequential, Concatenated Reed Solomon, TCM,
Turbo Product Code (TPC) (IESS-315 Compliant), LDPC Codeand VersaFEC (low-latency LDPC)• Widest Range of data interfaces: 4-port 10/100Base-T
Ethernet, EIA-422/530, V.35, G.703 T1, G.703 E1, G.703 T2,
G.703 E2, Quad G.703 E1, ASI, LVDS, HSSI• IEEE 1588v2 Precision Time Protocol• Sub Mux to multiplex IP/Ethernet traffic with serial or G.703
traffic• Drop & insert for T1/E1• Enhanced D&I++ for single T1/E1 & quad E1• Management: 10/100Base-T Ethernet with SNMP, Distant
End SNMP Proxy, HTTP, Telnet and EIA-232/EIA-485®
• Carrier ID using MetaCarrier Technology• Embedded Distant-end Monitor and Control (EDMAC)• Automatic Uplink Power Control (AUPC)• Engineering Service Channel (ESC/ESC++)• Standard high-stability internal reference-8(± 6 x 10 )• 5-tap Adaptive Equalizer• L-Band TX: 10 MHz reference for BUC, FSK communications
and optional BUC power supply• L-Band RX: 10 MHz reference and LNB power supply• L-Band: Advanced FSK for LPOD M&C• 1:1 and 1:10 redundancy switches available• Backwards compatible with CDM-625

Doubletalk Carrier-in-Carrier
DoubleTalk Carrier-in-Carrier, based on patented “Adaptive Cancellation” technology, allows transmit and receive carriers of a duplex
link to share the same transponder bandwidth. DoubleTalk Carrier-in-Carrier is complementary to all advances in modem technology,
including advanced FEC and modulation techniques. As these technologies approach theoretical limits of power and bandwidth
efficiencies, DoubleTalk Carrier-in-Carrier utilizing advanced signal processing techniques provides a new dimension in bandwidth
efficiency.

www.comtechefdata.com

Figure 1 shows the typical full-duplex satellite link, where the two carriers are adjacent to each other.
Figure 2 shows the typical DoubleTalk Carrier-in-Carrier operation, where the two carriers are overlapping, thus sharing the same
spectrum.

Figure 2

Figure 1

When observed on a spectrum analyzer, only the Composite is visible. Carrier 1 and Carrier 2 are shown in Figure 2 for reference only.
As DoubleTalk Carrier-in-Carrier allows equivalent spectral efficiency using a lower order modulation and/or code rate, it can reduce thepower required to close the link thereby reducing CAPEX by allowing a smaller BUC/HPA and/or antenna. Alternatively, DoubleTalk
Carrier-in-Carrier can be used to achieve very high spectral efficiencies E.g., DoubleTalk Carrier-in-Carrier when used with 16-QAM
approaches the bandwidth efficiency of 256-QAM (8 bps/Hz).
When combined with VersaFEC or LDPC/TPC, it can provide unprecedented savings in transponder bandwidth and power utilization.
This allows for its successful deployment in bandwidth-limited and power-limited scenarios, as well as reduction in earth station
BUC/HPA power requirements.
Carrier-in-Carrier® is a Registered Trademark of Comtech EF Data
DoubleTalk® is a Registered Trademark of Raytheon Applied Signal Technology
VersaFEC is a Registered Trademark of Comtech EF Data

Carrier-in-Carrier Automatic Power Control (CnC-APC)
The patent-pending Carrier-in-Carrier Automatic Power Control (CnC-APC) mechanism enables modems on both sides of a CnC link toautomatically measure and compensate for rain fade while maintaining the Total Composite Power. In addition to automaticallycompensating for rain fade, CnC-APC also enables the modems to share link margin, i.e. a modem in clear sky conditions caneffectively transfer excess link margin to a distant end modem experiencing fade, thereby further enhancing overall availability.

VersaFEC Forward Error Correction
CDM-625A-EN offers VersaFEC, a patent-pending system of high-performance LDPC codes designed to provide maximum coding gain
while minimizing latency. VersaFEC is designed to support ACM and CCM mode of operation
The Ultra Low Latency (ULL) codes provide even lower latency compared to standard VersaFEC codes.

Adaptive Coding & Modulation (ACM)
Satellite users have traditionally relied on worst case link margin to overcome rain fade which leads to significant inefficiencies. ACM
can provide significant increase in throughput as well as availability. ACM converts the fade margin into increased capacity making it
possible to more than double the throughput for Ku-band operation. Even under deep fade, ACM may be able to maintain the link at thelower MODCOD thereby increasing availability. It is tightly integrated with packet processor QoS which allows higher priority, mission
critical traffic to be maintained even during fade.

Low Density Parity Check Codes (LDPC) & Turbo Product Codes (TPC)nd

CDM-625A-EN offers an integrated LDPC and 2 Generation TPC codec. LDPC is an advanced Forward Error Correction techniquecapable of providing performance much closer to Shannon limit. The current LDPC implementation can provide 0.7 to 1.2 dB additional
coding gain compared to an equivalent TPC code.
In order to take full advantage of the increased coding gain provided by LDPC, Comtech EF Data has developed a patented 8-QAM
modulation that allows for acquisition and tracking at much lower Eb/No compared to 8PSK.

Dual Band Capability
CDM-625A-EN supports 70/140 MHz and extended L-Band (950 – 2250 MHz) capability in the same unit with independently selectabletransmit and receive IF. This simplifies sparing and stocking in networks requiring 70/140 MHz and L-Band units.

4-Port Managed Ethernet Switch with VLAN & QoS
CDM-625A-EN incorporates a 4-port 10/100Base-T managed Ethernet switch with VLAN capability and priority-based Quality ofService. Access (Native) Mode and Trunk Mode are supported. Traffic can be prioritized using port-based priority or VLAN priority. The
modem supports jumbo frames with maximum Ethernet frame size of 2048 bytes.

Packet Processor
The optional high-performance Packet Processor enables efficient IP networking and transport over satellite with low overhead
encapsulation, header compression, payload compression and advance Quality of Service to the CDM-625A-EN. The QoS combinedwith header and payload compression ensures the highest quality of service with minimal jitter and latency for real-time traffic, priority
treatment of mission critical applications and maximum bandwidth efficiency.
Packet processor supports Routed mode as well as Managed Switch Mode of operation. In managed switch mode, it operates as alayer 2 switch with VLAN support, enabling seamless integration with existing infrastructure while providing full optimization including
low overhead Streamline Encapsulation, header compression and payload compression and advanced QoS.
Header Compression
The Packet Processor incorporates industry-leading header compression for Ethernet and IP traffic. In managed switch mode, header
compression can reduce the 54 byte Ethernet/IP/UDP/RTP header to as little as 1 byte. For TCP/IP, the 54 byte header (including
Ethernet) is reduced to as little as 3 bytes. For applications such as VoIP, header compression can provide bandwidth savings
exceeding 65%. E.g. the 8 kbps G.729 voice codec requires 31.2 kbps once encapsulated into an Ethernet frame with IP/UDP/RTP.
With header compression, the same voice call needs about 9 kbps – a saving of almost 70%. And, bandwidth requirements for typical
Web/HTTP traffic can be reduced by 10% or more with TCP/IP header compression.
Payload Compression
The Packet Processor incorporates industry-leading GZIP based payload compression for IP/Ethernet traffic. Implemented in hardware
for maximum throughput and efficiency, payload compression can typically reduce the required satellite bandwidth by 30-40%.
Streamline Encapsulation (SLE)The Packet Processor incorporates Comtech EF Data’s patent-pending low overhead Streamline Encapsulation (SLE). SLE can reduce
the encapsulation overhead by as much as 65% compared to industry standard HDLC.
Advanced Quality of Service (QoS)
The Packet Processor incorporates multi-level QoS to ensure the highest quality service with minimal jitter and latency for real-timetraffic, priority treatment of mission critical applications and maximum bandwidth efficiency. Supported modes are:• DiffServ – Industry-standard method of providing QoS enabling seamless co-existence in networks that implement DiffServ• Max/Priority – Provides traffic prioritization with the ability to limit maximum traffic per priority class• Min/Max – Provides a Committed Information Rate (CIR) to each user defined class of traffic with the ability to allow a higher
burstable rate depending on availability
A powerful classifier supports packet classification by Protocol, VLAN ID / range, ToS Byte, Source IP (or subnet), Destination IP (orsubnet), Source Port (or Range), Destination Port (or Range) and DSCP (for DiffServ).

AES Data Encryption
Configurable on a per route basis, the modem supports AES data encryption for transmission security to prevent unauthorized accessto data transmitted over the satellite link. AES data encryption is only available for IP traffic processed by the Packet Processor.

Quad E1 Interface (QDI) with Enhanced D&I++
The CDM-625A-EN supports a Quad E1 interface that can aggregate up to four full or fractional E1s into a single carrier, with very low
overhead. This provides significant CAPEX savings by reducing the number of modems and could possibly reduce the BUC/HPA sizeby eliminating the multi-carrier backoff. A proprietary, closed network drop & insert (D&I++) allows for dropping or inserting any
combination of 1 to 31 time slots on each E1. D&I++ is supported for E1-CCS only.

IP Sub Multiplexer
The IP sub mux allows multiplexing IP/Ethernet traffic with serial or G.703 traffic into a single carrier. This is particularly useful forcellular backhaul when both E1 and IP backhaul is required. This reduces the number of modems and could possibly reduce the
BUC/HPA size by eliminating the multi-carrier backoff. The IP sub mux ratio ranges from 9:1 (IP data rate is 9 times that of the serial or
G.703 data rate) to as low as 1:59. IP sub mux can also be used to provision an overhead IP channel for management when using non
IP/Ethernet traffic interfaces.

EDMAC & AUPCThe CDM-625A-EN supports EDMAC, EDMAC-2, EDMAC-3 and AUPC. EDMAC/EDMAC-2/EDMAC-3 can be used to monitor andcontrol the distant end of a satellite link using a proprietary overhead channel. EDMAC-3 is also used for SNMP management of the
distant end modem. AUPC automatically adjusts modem transmit power based on feedback from the distant end modem to maintainthe desired Eb/No. AUPC and EDMAC are supported for point-to-point duplex links.

Management & SNMP Proxy
The modem can be managed via the front panel, the remote M&C port (EIA-232/EIA-485), or the 10/100Base-T Ethernet port. With
support for SNMP, HTTP and Telnet, the modem can be easily integrated into an IP-based management system. The CDM-625A-EN
can also act as SNMP proxy for the distant end CDM-625A-EN. This allows distant end CDM-625A-EN management using SNMP
without requiring an end-to-end IP link.

IEEE 1588v2 Precision Time Protocol (PTP)
PTP has emerged as the key technology for frequency, time and phase synchronization over a packet network. The CDM-625A-EN
incorporates hardware support for PTP, thereby significantly improving synchronization accuracy for satellite backhaul.

Advanced FSK for LPOD Monitoring & Control
The Advanced FSK allows for monitoring and control of LPOD through modem front panel menus, serial remote control and Telnet.

Feature Enhancements
Enhancing the capability of the CDM-625A-EN in the field is easy. Features that do not require additional hardware can be added onsite, using FAST access codes purchased from Comtech EF Data.

Specifications
Data Rate
Symbol Rate
Operating
Frequency
Major Operating
Modes(See User Manual
For Details)

FEC & Modulation
None
Viterbi: k=7, per
IESS-308/309
Viterbi with Reed
SolomonSequential
Reed Solomon
TCM (Per IESS310)
Integrated LDPC
ndand TPC (2 Gen)
Codec (Optional
Plug-in Module)

VersaFEC Codec(Option)

Scrambling

Management
Form C Relays
External Reference(Input OR Output)

18 kbps to 25 Mbps, in 1 bps steps(modulation, FEC & data interface dependant)
18 ksps to 12.5 Msps
50 – 180 MHz (standard) and
950 – 2250 MHz (option)
100 Hz resolution, independent TX and RX operation
Open network, per IESS-308 / 309 / 310 / 314
transparent, closed network per IESS-315
LDPC / TPC Codec (option)
VersaFEC Codec (option) with ACM or Constant Coding &Modulation (CCM)
EDMAC Framed with/without AUPC
RS Outer Codec
High rate ESC / Enhanced ESC (ESC++)
Drop & insert (D&I) /Enhanced D&I++ (option)
Quad E1 drop & insert (QDI) (option)
DoubleTalk Carrier-in-Carrier (option)
Uncoded BPSK/QPSK/OQPSK
Rate 1/2 BPSK/QPSK/OQPSK
Rate 3/4 QPSK/OQPSK
Rate 7/8 QPSK/OQPSK
Rate 3/4 16-QAM
Rate 7/8 16-QAM
See user manual for details
Open network and closed network modes
8PSK/TCM Rate 2/3
LDPC Code Rates
Rate 1/2 BPSK/QPSK/OQPSK
Rate 2/3 QPSK/OQPSK/8PSK/8-QAM
Rate 3/4 QPSK/OQPSK/8PSK/8-QAM/16-QAM
TPC Code Rates
Rate 5/16 BPSK
Rate 21/44 BPSK/QPSK/OQPSK
Rate 3/4 QPSK/OQPSK/8PSK/8-QAM/16-QAM
Rate 7/8 QPSK/OQPSK/8PSK/8-QAM/16-QAM
Rate 0.95 QPSK/OQPSK/8PSK/8-QAM
BPSK Rate 0.488
QPSK Rate 0.533, 0.631, 0.706, 0.803
8-QAM Rate 0.576 (ECCM), 0.642, 0.711, 0.780
16-QAM Rate 0.644 (ECCM), 0.731, 0.780, 0.829, 0.853
BPSK 0.493 (ULL)QPSK 0.493, 0.654, 0.734 (ULL)IDR Mode, no RS, - per ITU V.35 (Intelsat variant)
IBS mode, no RS - per IESS-309, externally frame
synchronizedTransparent Closed Network mode, no RS or Turbo coding per ITU V.35 (Intelsat variant)
EDMAC mode, no RS coding - externally frame
synchronized - proprietary
Turbo Product Code/LDPC/VersaFEC modes - externally
frame synchronized - proprietary
All RS modes - externally frame synchronized per IESS308/309/310
10/100Base-T Ethernet with SNMP, HTTP and Telnet
support, EIA-232, EIA-485 (2- or 4-wire)
Hardware fault, RX and TX traffic alarms, open network
backward alarms
BNC connector
Input: 1, 2, 5, or 10 MHz, -6 dBm to+10 dBm, 50 Ω/75 Ω (nominal)
Output: 10 MHz, 2.7 V peak-to-peak± 0.4 V, low impedance output

Data Interfaces
EIA-422/-530 DCE , Up to 14 Mbps
V.35 DCE , Up to 14 Mbps
LVDS Serial , Up to 25 Mbps
HSSI Serial , Up to 25 Mbps
G.703 T1, 1.544 Mbps
(Balanced 100 Ω)
G.703 T2, 6.312 Mbps
(Unbalanced 75 Ω or balanced
110 Ω)
G.703 E1, 2.048 Mbps
(Unbalanced 75 Ω or balanced
120 Ω)
G.703 E2, 8.448 Mbps (Unbalanced 75 Ω)
ASI , Up to 25 Mbps
Additional 2.048 Mbps E1 Ports for QuadE1 (Balanced 120 Ω)Overhead Data
Modem Alarms
4-port 10/100Base-T Managed Ethernet
Switch(With Packet Processor)

Modulator
Frequency Stability
Transmit Filtering
Alpha (Rolloff)
Harmonics and Spurious

Transmit On/Off Ratio
Output Phase Noise

Output PowerPower Accuracy

Output Impedance &Return Loss

Clocking Options

External TX Carrier Off
BUC Reference(10 MHz)BUC Power Supply(HW Option)

25-pin D-sub (female)
25-pin D-sub (female)

9-pin D-sub (female)or
BNC (female)

BNC (female)
9-pin D-sub (female)
44-pin High-density D-sub (male)
15-pin D-sub (male)
4 x RJ-45± 0.06 ppm (± 6 x 10-8), 0° to 50°C (32° to
122°F) with internal reference
Per IESS-308
5%, 10%, 15%, 20%, 25%, 35%
Better than -60 dBc/4 kHz(typically <-65 dBc/4kHz)
Measured from 1 to 500 MHz(50-180 MHz band)
Measured F0 ± 500 MHz(950-2250 MHz band)-60 dBc minimum< 0.480° rms double sided, 100 Hz to 1 MHz(Minimum 16 dB better overall than the Intelsat IESS308/309 requirements)
dB/Hz
Frequency Offset-63.0
100 Hz
-73.0
1 kHz
-83.0
10 kHz-93.0
100 kHz
Fundamental AC line spurious is -42 dBc or lower
The sum of all other single sideband spurious, from0 to 0.75 x symbol rate, is -48 dBc or lower
50-180 MHz:
0 to -25 dBm, 0.1 dB steps
950-2250 MHz:
0 to -40 dBm, 0.1 dB steps
50-180 MHz:± 0.5 dB over frequency, data rate, modulation type
and temperature range of 15 to 35° C± 0.8 dB over frequency, data rate, modulation type
and temperature range of 0 to 50° C
950-2250 MHz:± 0.7 dB over frequency, data rate, modulation type
and temperature range of 15 to 35° C± 1.0 dB over frequency, data rate, modulation type
and temperature range of 0 to 50° C
50-180 MHz: 50 Ω/75 Ω, 16 dB minimum return loss
(18 dB typical), BNC connector
950-2250 MHz: 50 Ω, 19 dB minimum return loss
(21 dB typical), Type-N connector
Internal, ± 0.06 ppm (SCT)
External, locking over a ± 100 ppm range (TT)Loop timing (RX satellite clock) – supports
asymmetric operation
External clock
By TTL ‘low’ signal or external contact closure
Via TX IF center conductor, 10.0 MHz± 0.06 ppm (with internal reference), selectable
on/off, 0.0 dBm ± 3 dB
24 VDC, 4.17 Amps max., 90 W @ 50° C
48 VDC, 3.125 Amps max., 150 W @ 50° C(180 W @ 30° C)
Supplied through TX IF center conductor andselectable on/off via M&C control

Demodulator
Input Power Range, Desired
Carrier

Max Composite Operating
Level

Absolute Maximum
Adaptive Equalizer
Acquisition Range
Below 64 ksymbols/sec
Between 64 and389 ksymbols/sec
Above 389 ksymbols/sec
Acquisition Time

Plesiochronous/
Doppler Buffer
Receive Clock
Clock Tracking
LNB Reference (10 MHz)LNB Voltage
Monitor Functions

Available Options
50-180 MHz: -105 + 10 log (symbol rate) to-70 + 10 log (symbol rate) dBm
950-2250 MHz: -130 + 10 log (symbol rate) to -80 +10 log (symbol rate) dBm
50-180 MHz:
94 – 10 log (symbol rate, desired carrier) dBc, +10
dBm max., with the additional requirement thatwithin ± 10 MHz of the desired carrier thecomposite power is ≤ +30 dBc
950-2250 MHz:
102 – 10 log (symbol rate, desired carrier) dBc, +10
dBm max., with the additional requirement thatwithin ± 10 MHz of the desired carrier thecomposite power is ≤ +30 dBc+20 dBm
5-tap design, selectable on/off
Programmable in 1kHz increments± 1 kHz to ± (Rs/2) kHz, where Rs = symbol rate in
ksymbols/sec± 1 kHz to ± 32 kHz± 1 kHz to ± (0.1 * Rs) kHz, up to a maximum of ±200 kHz
Highly dependent on data rate, FEC rate, anddemodulator acquisition range.
E.g. 120 ms average at 64 kbps, R1/2 QPSK, ± 10
kHz acquisition sweep range,
6 dB Eb/No
Selectable from 64 to 262,144 bits, in 16-bit steps(Additional limitations for G.704 frame boundaries)
RX satellite, TX terrestrial, external reference± 100 ppm minimum
Via RX IF center conductor, 10.0 MHz± 0.06 ppm (with internal reference), selectable
on/off, -3.0 dBm ± 3 dB
Selectable on/off, 13 VDC, 18 VDC per DiSEq 4.2
and 24 VDC at 500 mA maximum
Eb/N0 estimate, corrected BER, frequency offset,
buffer fill state, receive signal level

HardwareHardwareHardwareHardwareHardwareHardware
FAST
FAST
FAST
FAST
FAST
FAST
FAST
FAST
FAST
FAST
FAST
FAST
FAST
FAST
FAST
FAST
FAST

100 – 240 VAC, 175 W AC primary power supply-48 VDC, 125 W primary power supply-24 VDC, 120 W primary power supply
24 VDC, 90 W @ 50°C BUC power supply, AC, 24 VDC or 48 VDC
primary power supply
48 VDC, 150 W @ 50°C (180 W @ 30°C) BUC power supply, AC or
48 VDC primary power supplyndIntegrated TPC (2 generation) and LDPC Codec module
L-Band IF (in addition to 70/140 MHz)
Modem data rate – 10 Mbps, 15 Mbps, 20 Mbps or 25 Mbps
8PSK and 8-QAM modulation (8-QAM requires TPC/LDPC or
VersaFEC Codec)
16-QAM modulation
TPC/LDPC Codec data rate – 10 Mbps, 15 Mbps, 20 Mbps or 25
Mbps
Activate DoubleTalk Carrier-in-Carrier Feature
DoubleTalk Carrier-in-Carrier Data Rate (full) – 512 kbps, 1.1 Mbps,
2.5 Mbps, 5 Mbps, 10 Mbps, 15 Mbps, 20 Mbps or 25 Mbps
DoubleTalk Carrier-in-Carrier Data Rate (fractional) – 2.5 Mbps, 5
Mbps, 10 Mbps, 15 Mbps, 20 Mbps or 25 Mbps
VersaFEC Codec data rate (CCM) – 1.1 Mbps, 2.5 Mbps, 5 Mbps or
16 Mbps
VersaFEC Codec symbol rate (ACM) – 300 ksps, 1.2 Msps or
4.1 Msps
Open network – IBS with high rate IBS ESC, IDR and audio
D&I / D&I++ for single Port T1/E1
D&I++ For Quad E1 Port 2, 3 and 4
Quality of Service
Header Compression
Payload Compression
Advanced Network Timing (IEEE 1588v2 PTP)

Accessories
CRS-170A
CRS-180
CRS-500
CRS-282XXX

1:1 Modem Redundancy Switch (L-Band)
1:1 Modem Redundancy Switch (70/140 MHz)
1:N Modem Redundancy System(For use with Packet Processor Only)
1:10 IF Redundancy Switch(For use with CRS-500)

DoubleTalk Carrier-in-Carrier

Environmental and PhysicalDelay Range
Power Spectral Density
Ratio(Interferer to Desired)
Maximum Symbol Rate
Ratio
Eb/No Degradation

Temperature

Satellite Restrictions

0 to 330 ms
BSPK/QPSK/8PSK/8-QAM: –7 dB to+11 dB
16-QAM: -7 dB to +7 dB
3:1 (TX:RX or RX:TX)
0 dB Power Spectral Density Ratio
BPSK/QPSK/OQPSK: 0.3 dB
8-QAM: 0.4 dB
8PSK: 0.5 dB
16-QAM: 0.6 dB+10 dB power spectral density ratio
Additional 0.3 dB
Satellite in “loop-back” mode (i.e., the transmit
station can receive itself)“Non-processing” satellite (i.e., does notdemodulate or remodulate the signal)

Power Supply

Dimensions (1RU)(height x width x
depth)
Weight
CE Mark

FCC

Operating: 0 to 50°C (32 to 122°F)
Storage: -25 to 85°C (-13 to 185°F)
100 – 240 VAC, +6%/-10%, 50/60 Hz, auto sensing-24 VDC (HW option)-48 VDC (HW option)
1.75” x 19.0” x 17.65”(4.4 x 48 x 44.8 cm) approximate
10.8 lbs (4.9 kg) maximum, with all option modules and
48 VDC BUC power supply installed
EN 301 489-1 (ERM)
EN55022 (Emissions)
EN55024 (Immunity)
EN 61000‐3‐2
EN 61000‐3‐3
EN60950 (Safety)
FCC Part 15, Subpart B

2114 West 7th Street, Tempe, Arizona 85281 USA
Voice: +1.480.333.2200 ● Fax: +1.480.333.2540 ● Email: sales@comtechefdata.com
See all of Comtech EF Data’s Patents and Patents Pending at http://patents.comtechefdata.com
Comtech EF Data reserves the right to change specifications of products described in this document at any time without notice and without obligation to notify any person of such changes. Information inthis document may differ from that published in other Comtech EF Data documents. Refer to the website or contact Customer Service for the latest released product information© 2013 Comtech EF Data
ds-CDM-625A-EN.docx
10/1/2013