Comtech CDM-760

The CDM-760 Advanced High-Speed Trunking and Broadcast Modem builds on our award-winning family of high-speed, ultra efficient trunking modems. The CDM-760 further enhances our offerings to include ultra wide band symbol rates, near theoretical performance with minimal implementation loss, a variety of high efficiency MODCOD selections. Configurable as a true DVB-S2&S2X broadcast modulator, demodulator or Modem and supports HTS, GEO and MEO mode operation with hitless antenna handover and satellite handover. 

The CDM-760 Advanced High-Speed Trunking and Broadcast Modem was designed to be the most efficient, highest throughput, point-to-point modem available. Accommodating the most demanding Internet Service Providers, Broadcasters and telco backhaul links by offering users the most advanced combination of space segment saving capabilities while minimizing overhead. 

The CDM-760 offers an expansive range of symbol rates (100 ksps to 150 Msps) and data rates (100 kbps to >720 Mbps) simplex. In a duplex setting, this is >1.4 Gbps or 300 Msps. The onboard Ethernet interfaces support Super Jumbo Frames from 64 Bytes to >10,000 Bytes and will process Ethernet frames at a blazing > 1.2 Million packets / second. With the optional Packet Processor card installed the CDM-760 can support > 350,000 packets per second while performing simultaneous Header Compression and QoS. 

Comtech offers a variety of open or closed network specifications and MODCOD selections. The CDM-760 can be configured to run as DVB-S2 (EN 302 307), DVB-S2X (EN 302 307-2) open standard waveforms, or with Comtech’s DVB-S2-EB1& EB2 (Efficiency Boost) waveforms. All waveforms are interoperable with ACM and the CDM-760 DPD (Dynamic Pre-Distortion). DPD allows satellite amplifiers to push further into saturation, maximizing transponder efficiency. The pre-distortion function is constantly optimized by the modem and does not require any user intervention. 

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. 

An optional high-speed packet processor card has a powerful user-defined QoS engine for traffic shaping, performing header compression (greatly reducing WAN capacity with smaller packets >60%), and enables static routing. The optional K4 GZIP lossless compression engine performs real-time compression of user payload. Performance testing shows a 52% to 59% compression rate when tested against an industry standard Calgary Corpus profile. 

DVB-CID ETSI TS 103 129 is the ETSI standard for combating satellite interference and is largely based on Comtech EF Data’s award-winning MetaCarrier® technology. MetaCarrier technology embeds and detects a small message and unique ID within a video or data satellite carrier. This embedded message and ID significantly reduce the time to identify and clear interference sources. 

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, Broadcaster and telco operator. When used in combination, however, the capacity savings cannot be matched. 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.