Comtech EF Data CDM-760 Advanced High-Speed Trunking Modem

Comtech EF Data CDM-760 Advanced High-Speed Trunking Modem

L-Band Modems

CDM-760 FEATURES Symbol Rate: 0.1 to 150 Msps Data Rate: 0.1 to 314 Mbps DVB-S2 ETSI EN 302 307 compliant DVB-S2-EB1 Efficiency Boost technology DoubleTalk Carrier-in-Carrier bandwidth compression ACM and CCM GSE – low overhead <1% encapsulation Super Jumbo Frame...

  • Category: All Products, Comtech EF Data, L-Band Modems, Satellite Modems - VSATplus


  • Symbol Rate: 0.1 to 150 Msps
  • Data Rate: 0.1 to 314 Mbps
  • DVB-S2 ETSI EN 302 307 compliant
  • DVB-S2-EB1 Efficiency Boost technology DoubleTalk Carrier-in-Carrier bandwidth compression
  • ACM and CCM
  • GSE – low overhead <1% encapsulation
  • Super Jumbo Frame 10,240 Byte Support
  • Modulation: QPSK, 8PSK, 16APSK, 32APSK
  • Dual IF: 70/140 MHz, L-Band and L-Band monitor (standard)
  • Data Interfaces
    • 2 Gigabit 10/100/1000Base-T interfaces (standard)
    • 1 Optical Gigabit interface (optional)
    • Processes > 600,000 pps simplex, 1.2M pps duplex
    • PIIC optional interface cards
    • G.703 E3/T3/STS-1 (34.368, 44.736, 51.84 Mbps)
    • STM-1 Copper SDH (155.52 Mbps)
    • OC-3 SONET single mode or multi-mode 1300 nm (155.52 Mbps)
  • Multistream capable (Multi-Interface mux)
  • Management: HTTP, SNMP, Telnet, RS 232/485
  • In-band (over satellite) M&C control
  • 1:1 and 1:N redundancy switching available


*Note: Contact our Sales Engineer for information on Configuration and Pre-Sale Pricing.

The CDM-760 offers an expansive range of symbol rates (1 ksps to 150 Msps) and data rates (100 kbps to 314 Mbps). Run in a duplex setting, this is a staggering 628 Mbps or 300 Msps. Coupling these speeds with the native Super Jumbo Frame Ethernet interfaces supporting Ethernet frames from 64 Bytes to >10,000 Bytes and the CDM-760 will process Ethernet frames at a blazing (> 1.2 Million packets / second).


  • Mobile Operators
  • Telecom Operators
  • ISPs
  • Government & Military


  • IP Trunking
  • G.703 Trunking
  • High-Speed Content Delivery
  • Disaster Recovery & Emergency Communications

Expanding on the efficient DVB-S2 EN 302 307 standard, the CDM-760 again furthers spectral efficiency with its DVB-S2-EB1 (Efficiency Boost) waveforms. DVB-S2 is widely accepted as the most spectrally efficient standards-based waveforms. With our Efficiency Boost technology (DVB-S2-EB1), you can achieve a 10% – 35% increase in efficiency over the DVB-S2 standard without an increase in power or occupied bandwidth. The CDM-760 accomplishes this task by virtually doubling the number of available MODCODs, introducing three new ROF figures (5%, 10% and 15%) and minimizing implementation loss to near theoretical operation. The CDM-760 is software upgradeable to support future standards including DVB-S2 Efficiency Boost, DVB-S2 Extension and DVB-S3.

Implementing Adaptive Coding and Modulation (ACM) operation allows link margin to be converted to user capacity during non-faded conditions by taking advantage of the actual signal to noise ratio rather than calculated worst case signal to noise.

By using the best encapsulation methods, the CDM-760 further increases throughput by using minimal overhead. In G.703 synchronous mode, users can implement monitor and control over the satellite with no additional overhead. When using Ethernet bridge mode, less than 1% overhead is used for encapsulation.

Additionally, the CDM-760 leverages our powerful DoubleTalk® Carrier-in-Carrier® “Adaptive Cancellation” technology. With the ability to overlay TX and RX carriers, Carrier-in-Carrier enables the operator to establish the perfect balance between bandwidth and power, enabling the best possible use of the satellite resource and reducing operating expenses (OPEX).

These technologies alone offer enormous savings to the ISP and telco operator. When used in combination, however, the savings are astronomical. The innovative high-performance architecture of the CDM-760 allows efficient networking and transport over satellite links while supporting a wide range of applications and network topologies.


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.

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 efficiency, DoubleTalk Carrier-in-Carrier utilizing advanced signal processing techniques provides a new dimension in bandwidth and power efficiency.

DoubleTalk Carrier-in-Carrier allows satellite users to achieve spectral efficiencies (i.e. bps/Hz) that cannot be achieved with traditional links. E.g., 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.

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.