Comtech EF Data Introduces Point-To-Multipoint Modem, Low-Latency ACM

Comtech EF Data unveiled its new CDM-740 Satellite Modem – a high performance architecture featuring an integrated DVB-S/S2 receiver and a turbo product-coding Single Carrier Per Channel (SCPC) Modulator, the company announced.

  Comtech EF Data said that the combination of a shared, high speed outbound DVB-S/S2 carrier and TPC for the low latency data return channel aims to facilitate efficient IP networking and transport over satellite.

  Optimized for high-speed packet processing and reliability, Comtech said its CDM-740 product uses an embedded central processing unit, real time operating system and flash data storage, while offering dual Gigabit Ethernet interfaces.The system transmits industry-standard TPC up to 9.98 Mbps. The receive side supports DVB-S and DVB-S2 operation at L-Band up to 62 Msps.

   Comtech has also rolled out an adaptive coding and modulation (ACM) capability for its CDM-625 advanced satellite modem, which is optimized by pairing the system with Comtech’s forward error correction device, VersaFEC, the company announced July 8.

   The combination of the systems is being marketed to VSAT end-users as a lower-latency alternative to a DVB-S2 and ACM combination.

   Comtech said that when compared to DVB-S2 paired with ACM, which uses a constant number of bits per frame, the combination of VersaFEC and ACM provides a reduction in system latency, enabling more bandwidth efficiency and increasing throughput for IP-based point-to-point applications.

   ACM works to automatically adapt a signal modulation type and forward error correction code rate to provide the highest possible throughput, regardless of link conditions.