Modems CDM-Qx & CDM-QxL Multi-Channel Satellite Modems with

CDM-Qx & CDM-QxL Multi-Channel
Satellite Modems with
DoubleTalk® Carrier-in-Carrier®
Modems
Overview
The CDM-Qx and CDM-QxL Multi-Channel Satellite Modems offer DoubleTalk Carrier-in-Carrier
bandwidth compression capability, allowing transmit and receive carriers of a full-duplex satellite link to
share the same transponder space. DoubleTalk Carrier-in-Carrier enables multi-dimensional optimization,
thereby allowing satellite communications users to:
 Reduce operating expenses (OPEX)
 Increase throughput without using additional transponder resources
 Increase availability (margin) without using additional transponder resources
 Reduce capital expenses (CAPEX) by allowing a smaller BUC/HPA and/or antenna
 Or, a combination to meet specific user needs
Typical Users
• Satellite Service
Providers
• Fixed Line Operators
• Service Providers
• Government & Military
Features
• Enterprise
 DoubleTalk Carrier-in-Carrier bandwidth compression
 Four slot chassis, allowing flexible configuration
• Oil Field Service
Providers
 CDM-Qx: 50 to 90, 100 to 180 MHz
CDM-QxL: 950 to 1950 MHz
Common Applications
 Data Rate: 32 kbps to 20 Mbps
 Modulation: BPSK, QPSK, 8PSK and 16-QAM
• Cellular Backhaul
 Forward Error Correction (FEC): Viterbi, Concatenated Reed Solomon and Turbo Product Coding
(TPC) (IESS-315 Compliant)
• G.703 Trunking
 Data Interface: EIA-422, V.35, Sync EIA-232, G.703 T1, G.703 E1, Quad G.703 E1, G.703 E2 and
HSSI
• Offshore & Maritime
 Enhanced D&I++ for Single & Quad E1
Communications
 M&C: EIA-232, EIA-485, and 10/100Base-T Ethernet with SNMP, HTTP and Telnet support
 Embedded Distant-end Monitor and Control (EDMAC)
 Automatic Uplink Power Control (AUPC) Spectrum Analyzer Function
 Asymmetric Loop Timing
 Common frequency reference for all modules
 Individual modulator output power control
 CDM-QxL: 10 MHz reference for BUC, FSK communications and optional BUC power supply
 CDM-QxL: 10 MHz reference and LNB power supply
 Interoperable with many Comtech EF Data satellite modems: CDM-550T, 570, 570L, 600, 600L, SDM-8000, 300A, and 300L3
Turbo Product Coding
The CDM-Qx/QxL offer 2nd generation Turbo Product Codec as an option. TPC provides increased coding gain with low decoding delay.
Combined with DoubleTalk Carrier-in-Carrier, they provide unprecedented savings in transponder bandwidth and power utilization as well
as earth station BUC/HPA size.
QUAD E1 Interface (QDI) with Enhanced D&I++
The CDM-Qx/QxL supports a Quad E1 interface that can aggregate up to four synchronous full or fractional E1s into a single carrier, with
very low overhead. This provides significant CAPEX savings by reducing the number of modems and the simultaneous reduction in
BUC/HPA size due to the elimination of 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.
BUY NOW
Doubletalk Carrier-In-Carrier
DoubleTalk Carrier-in-Carrier is based on patented bandwidth compression technology originally developed by Applied Signal
Technology, Inc. Using “Adaptive Cancellation” it allows transmit and receive carriers of a two-way link to share the same transponder
space.
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 1
Figure 2
When observed on a spectrum analyzer, only the Composite is visible. Carrier 1 and Carrier 2 are shown in Figure 2 for reference only.
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.
DoubleTalk Carrier-in-Carrier allows satellite users to achieve spectral efficiencies (i.e. bps/Hz) that cannot be achieved with traditional
links. For example, DoubleTalk Carrier-in-Carrier when used with 16-QAM approaches the bandwidth efficiency of 256-QAM (8bps/Hz).
As DoubleTalk Carrier-in-Carrier allows equivalent spectral efficiency using a lower order Modulation and/or FEC Code, it can
simultaneously reduce CAPEX by allowing a smaller BUC/HPA and/or antenna.
DoubleTalk Carrier-in-Carrier can be used to save transponder bandwidth and/or transponder power thereby allowing successful
deployment in bandwidth-limited as well as power-limited scenarios. The following example illustrates the typical process for
implementing DoubleTalk Carrier-in-Carrier in a power-limited scenario:
The conventional link is using 8PSK, TPC 3/4:
A
B
B
Spread the signal by switching to a lower order modulation and/or FEC
code – say QPSK, TPC 7/8. This increases the total transponder
bandwidth, while reducing the total transponder power:
A
Now using DoubleTalk Carrier-in-Carrier, the second QPSK, TPC 7/8 carrier can be moved over the first carrier – thereby reducing the
total transponder bandwidth and total transponder power when compared to the original side-by-side 8PSK, TPC 3/4 carriers:
Carrier-in-Carrier® is a Registered Trademark of Comtech EF Data
DoubleTalk® is a Registered Trademark of Raytheon Applied Signal Technology
EDMAC & AUPC
The CDM-Qx/QxL support EDMAC, EDMAC-2, and AUPC. EDMAC/AUPC is compatible with CDM-600/600L and CDM-570/570L.
EDMAC-2/AUPC is compatible with CDM-570/570L.
Monitoring & Control
The CDM-Qx/QxL provide a range of options for local and remote management. 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 modems can be
easily integrated into an IP-based management system.
Feature Enhancements
Enhancing the capability of CDM-Qx/QxL 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.
Data Interfaces
The CDM-Qx/QxL support a range of data interfaces – EIA-422, V.35, Sync EIA-232, G.703 T1, G.703 E1, Quad G.703 E1, G.703 E2
and HSSI.
CDM-Qx Shown With:
Slot 1
Modulator Card with G.703 Balanced Interface
Slot 2
Modulator Card with G.703 Balanced Interface
Slot 3
Modulator Card with EIA-530 Interface
Slot 4
Modulator Card with EIA-530 Interface
Notes:
 Also shown, placed above the CDM-Qx are the modulator and demodulator cards with G.703 Unbalanced (BNC) interface.
 Typically each modulator and demodulator card requires a data interface. However, if configured as a modem, only the demodulator
card requires a data interface.
 Unlike other data interfaces, the Quad E1 interface requires 2 slots in the CDM-Qx/QxL chassis
Specifications
Data Rate
(See Summary Table)
Symbol Rate
Scrambling
FEC
(See Summary Table)
Turbo Product Coding
(TPC) nd
2 Generation
M&C Interface
Form C Relays
External Reference
IF Impedance &
Connectors
Monitor Functions
32 kbps to 20 Mbps, in 1 bps steps
(data interface dependant)
Up to 10 Msps
V.35, or synchronous
Viterbi 1/2, 3/4 and 7/8
Concatenated Reed-Solomon 1/2, 2/3, 3/4, and
7/8
Hardware option
BPSK Rate 5/16 and 21/44
QPSK Rate 21/44, 3/4, 7/8, and 17/18
8PSK Rate 3/4, 7/8, and 17/18
16-QAM Rate 3/4 and 7/8
EIA-232, EIA-485 (2- or 4-wire),
10/100 Base-T Ethernet with SNMP, HTTP and
Telnet support
TX, RX traffic alarms and unit faults
1, 2, 5, 10 or 20 MHz, BNC connector
CDM-Qx: 75  (Optional 50 ), BNC female
CDM-QxL: 50 , Type-N female
Eb/N0, Frequency Offset, BER, buffer fill status,
RX signal level, carrier power ratio
Demodulator
Frequency Range
Input Power
Automatic Gain Control
Max Composite Level
Acquisition Range
Modulator
Frequency Range
Frequency Stability
Harmonics and
Spurious
Transmit On/Off Ratio
Phase Noise
Output Power (per
Modulator)
Power Accuracy
External Carrier Off
BUC FSK
Communications
BUC Power Supply
CDM-Qx: 50 to 90, 100 to 180 MHz
CDM-QxL: 950 to 1950 MHz
100 Hz frequency resolution (both)
CDM-Qx:  1.0 ppm (standard),  0.1 ppm
(optional), 0 to 50ºC (32 to 122ºF)
CDM-QxL:  0.1 ppm, 0 to 50ºC (32 to 122ºF)
<-55 dBc/4 kHz (typically <-60 dBc/4 kHz)
55 dB minimum
< 0.75 degrees RMS double-sided,
100 Hz to 1 MHz
CDM-Qx: -5 to -25 dBm, 0.1 dB step
CDM-QxL: -5 to -45 dBm, 0.1 dB step
 1 dB over frequency and temperature
By TTL low signal
CDM-QxL: Via TX center conductor with FSK
capable BUCs
CDM-QxL: None, 24 VDC, 48 VDC (option)
Receive Buffer
Receive Clock Options
Clock Tracking
LNB Voltage
CDM-Qx: 50 to 90, 100 to 180 MHz
CDM-QxL: 950 to 1950 MHz
100 Hz frequency resolution (both)
CDM-Qx:
-15 to -45 dBm, < 2.048 Msps
-15 to -40 dBm, > 2.048 Msps < 4.096 Msps
-15 to -35 dBm, > 4.096 Msps
CDM-QxL:
-130 + 10log(symbol rate) dBm (minimum)
CDM-QxL: 50 dB
CDM-Qx: +35 dBc, up to -5 dBm,
+76 – 10log(symbol rate) dBc within 10 MHz
of desired carrier
CDM-QxL: +87 – 10log(symbol rate) dBc
(Broadband), +76 – 10log(symbol rate) dBc
within 10 MHz of desired carrier, -5 dBm
absolute maximum
CDM-Qx:  1 to  32 kHz, programmable, in 1
kHz steps (symbol rate > 64 ksps)
 1 to  (SR/2) kHz, programmable, in
1 kHz steps (symbol rate <= 64 ksps)
CDM-QxL:  1 to  200 kHz, programmable,
in 1 kHz steps (symbol rate > 625 ksps)
 1 to  32 kHz, programmable, in 1 kHz
steps (64 ksps < symbol rate < 625 ksps)
 1 to  (SR/2) kHz, programmable, in
1 kHz steps (symbol rate <= 64 ksps)
512, 1024, 2048, 4096, 8182, or 16384 bits
RX satellite, TX terrestrial, external reference
 100 ppm minimum
CDM-QxL: Off, 13 VDC or 18 VDC, 500 mA
(max.)
DoubleTalk Carrier-in-Carrier
Minimum Symbol Rate
Propagation Delay
Max Symbol Rate Ratio
(See Whitepaper)
Max Power Ratio
(See Whitepaper)
Satellite Restrictions
256 ksps
0 to 330 ms
3:1 (TX:RX or RX:TX)
TX carrier power (interferer) – RX carrier
power (desired), in dB, < 10 dB
(except for 16-QAM, TPC, R=7/8)
TX carrier power (interferer) – RX carrier
power (desired), in dB, < 7 dB
(16-QAM, TPC, R=7/8)
Satellite in “loop-back” mode (i.e. TX station
must be able to receive itself)
“Non-processing” satellite (i.e. does not
demodulate/remodulate the signal)
FEC, Modulation & Data Rate Summary
FEC Type
Modulation
Viterbi
Viterbi
Viterbi
Viterbi
Viterbi + RS (201/219)
Viterbi + RS (201/219)
Viterbi + RS (201/219)
Viterbi + RS (201/219)
Viterbi + RS (201/219)
Viterbi + RS (201/219)
BPSK
QPSK
QPSK
QPSK
BPSK
QPSK
QPSK
QPSK
16-QAM
16-QAM
TCM + RS (201/219)
8PSK
TCP
TCP
TCP
TCP
TCP
TCP
TCP
TCP
TCP
TCP
TCP
*Unframed operation
BPSK
BPSK
QPSK
QPSK
QPSK
QPSK
8PSK
8PSK
8PSK
16-QAM
16-QAM
Code
Rate
1/2
1/2
3/4
7/8
1/2
1/2
3/4
7/8
3/4
7/8
2/3
5/16
21/44
21/44
3/4
7/8
17/18
3/4
7/8
17/18
3/4
7/8
Environmental And Physical
Data Rate Range*
32 kbps – 5 Mbps
32 kbps – 10 Mbps
32 kbps – 15 Mbps
32 kbps – 17.5 Mbps
32 kbps – 4.5 Mbps
32 kbps – 9.1 Mbps
32 kbps – 13.7 Mbps
32 kbps – 16 Mbps
352.4 kbps – 20 Mbps
411.1 kbps – 20 Mbps
234.9 kbps – 18.3
Mbps
32 kbps – 3.1 Mbps
32 kbps – 4.7 Mbps
32 kbps – 9.5 Mbps
32 kbps – 15 Mbps
32 kbps – 17.5 Mbps
32 kbps – 18.8 Mbps
288 kbps – 20 Mbps
336 kbps – 20 Mbps
362.7 kbps – 20 Mbps
384 kbps – 20 Mbps
448 kbps – 20 Mbps
Temperature
Power Supply
Power
Consumption
Dimensions (1RU)
(height x width x
depth)
Weight
CE Mark
FCC
Single G.703 E1
Frame Format
Time Slots
Interoperability
Quad G.703 E1
Frame Format
Time Slots
Framing
Overhead
Interoperability
EMC
Safety
Part 15
Available Options- Chassis
How Enabled
Hardware
Hardware
Hardware
Hardware
Hardware
Hardware
Enhanced D&I++ for G.703 E1
Operating: 0 to 50ºC (32 to 122°F)
Storage: -25 to 85ºC (-13 to 185ºF)
100 to 240 VAC, 50/60 Hz, auto sensing
-48 VDC (option)
CDM-Qx: < 90 W typical
(Depending on configuration)
CDM-QxL: < 90 W typical, w/o BUC PS
(Depending on configuration)
CDM-Qx:
1.75” x 19.0”” x 19”
(4.4 x 48 x 48 cm) approximate
< 20 lbs (7.0 kg) approximate
(Depending on configuration)
Option
75 or 50  IF connector (CDM-Qx only)
Redundant primary power supply
0.1 ppm reference (CDM-Qx only)
-48 VDC power supply
BUC PS 24 VDC, 80 W @ 50°C, 100 W @ 30°C, AC
or DC input (CDM-QxL only)
BUC PS 48 VDC, 150 W @ 50°C,180 W @ 30°C, AC
or DC input (CDM-QxL only)
1:1, 1:2, or 1:3 Internal Redundancy*
DoubleTalk Carrier-in-Carrier to 512 kbps
DoubleTalk Carrier-in-Carrier to 1 Mbps
DoubleTalk Carrier-in-Carrier to 2.5 Mbps
DoubleTalk Carrier-in-Carrier to 5 Mbps
DoubleTalk Carrier-in-Carrier to 10 Mbps
DoubleTalk Carrier-in-Carrier to 20 Mbps
Enhanced D&I++ for one/both modems
E1-CCS Only
Any combination of 1 to 31 time slots can be
dropped or inserted
Interoperable with CDM-600/600L for
combinations of up to 24 time slots (E1-CCS frame
format, Viterbi and TPC FEC only).
FAST
FAST
FAST
FAST
FAST
FAST
FAST
FAST
E1-CCS Only
For each E1, any combination of 1 to 31 time slots
can be dropped or inserted
0.4% (EDMAC/AUPC additional if needed)
* 1:1 Internal Redundancy for Modem
1:1 or 1:2 or 1:3 Internal Redundancy for Modulator/Demodulator
Quad G.703 E1 Only
Ber Performance
Met with two adjacent carriers 7 dB higher at 1.3 channel spacing
Guaranteed Eb/N0, in dB
Consult the CDM-Qx Manual for a comprehensive listing of the
performance of all FEC types, Code Rates, Modulation types, and
Data Rate ranges.
TPC
BPSK
QPSK
5/6
21/44
21/44
3/4
7/8
17/18
-6
10
2.4
2.9
3.5
3.8
4.3
6.8
-8
10
2.8
3.3
3.6
4.4
4.5
7.4
TPC
8PSK
16-QAM
3/4
7/8
17/18
3/4
7/8
-6
10
6.2
7.0
9.3
7.4
8.1
-8
10
6.8
7.2
10.3
8.2
8.3
Refer to the Whitepaper for Eb/No Degradation due to DoubleTalk
Carrier-in-Carrier.
A white paper, DoubleTalk Carrier-in-Carrier Bandwidth Compression
Providing Significant Improvements in Satellite Transponder Bandwidth, is
available on the Comtech EF Data web site on the White Papers page,
under All Collateral.
Modulator/Demodulator/Interface
How Enabled
Hardware
Hardware
Hardware
Hardware
Hardware
Hardware
Hardware
FAST
FAST
FAST
FAST
Option
nd
2 Generation Turbo Product Coding module
25-Pin EIA-422, V.35 or Sync EIA-232 interface*
G.703 E1/T1 balanced interface*
G.703 E1/T1 unbalanced interface*
G.703 E2 unbalanced interface*
HSSI interface*
Quad G.703 E1 interface**
Data rate to 10 Mbps
Data rate to 20 Mbps
8PSK
16-QAM
* A data interface is only needed for the demodulator card when the
modulator and demodulator are used together as a modem. In this
case, all input and output data is routed through the demodulator’s
data interface.
** Unlike other data interfaces, Quad G.703 E1 interface requires 2 full
slots (3 and 4) in the CDM-Qx/QxL chassis.
Accessories
CRS-311-Qx
CRS-300-Qx
1:1 Modem Redundancy Switch
1:10 Modem Redundancy Switch
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 in this
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.
© 2012 Comtech EF Data
ds-cdmqx.docx
2/23/2012