Written by / Compiled by KMI Media Group staff
Forward Error Correction Supports Latency-Sensitive Applications
Comtech EF Data has announced VersaFEC, the next generation forward error correction (FEC). VersaFEC provides maximum coding gain with the lowest possible latency to support cellular backhaul and other latency-sensitive voice, video and data applications. VersaFEC is available as a plug-in module for the CDM-625 Advanced Satellite Modem. VersaFEC is a system of short-block, low latency Low Density Parity Check (LDPC) codes designed to support latency-sensitive applications. Designed to provide maximum coding gain while minimizing the end-to-end latency, VersaFEC provides an excellent alternative to existing LDPC and DVB-S2 codes. This next generation FEC provides an expanded choice of modulation and code combinations (ModCods). The 12 ModCod combinations offer equivalent coding gains to Comtech EF Data’s existing LDPC offering, and significantly reduce latency.
Voice Transport Module Supports Land Mobile Radios
The Harris VF-40 is a new voice transport module for land mobile radio (LMR) networks. The VF-40 works with Harris Intraplex Access Server multiplexers for T1 or E1 network applications and with Intraplex NetXpress multiplexers for IP networks. Targeted at state and municipal safety agencies, the VF-40 includes features to improve the efficiency of multichannel land mobile radios and the interconnection of LMR dispatch sites and transmission towers. One of the major improvements of the VF-40 over older technologies is that it enables unobtrusive sharing of radio channels among multiple user groups by passing continuous tone coded squelch system tones—or private line tones—ranging in frequency from 67 Hz to 254 Hz. These low-frequency tones are carried through the four-wire audio channel along with the voice signal. The VF-40 provides two independent contact-closure signaling lines in both transmission directions for each of the four voice channels to support efficient multichannel LMR installations, transporting push-to-talk, facility alarms, receiver un-squelch status or other signals. This transport of up to eight signaling leads in each direction per module increases the efficiency of LMR infrastructure bandwidth use and simplifies system design.
Intelligence Gateways Provide Enhanced Transport
Network Equipment Technologies has announced the general availability of a new release of software for its VX series of intelligent gateways. This release provides enhanced transport of modem signals across the IP network for secure telephone equipment using the V.150 standard and advanced call control using the government’s multi-level precedence and preemption (MLPP) standard. The V.150 capability, when combined with the VX series’ existing ability to support TDM-based Secure Terminal Equipment and Secure Communications Interoperability Protocol phones, enables instant interoperability between old and new technologies. NET’s V.150 solution interoperates with NET’s Bestflow frame-packing technique, which allows VoIP to traverse firewalls without violating security policies, while providing significant bandwidth-saving capabilities and numerous features that protect the reliability of secure telephony over IP. NET now supports the Department of Defense’s MLPP implementation over both packet and circuit networks. MLPP allows call precedence values to be enforced when networks exhibit resource contention or bandwidth limitations. NET’s implementation of MLPP provides a robust and secure solution for MLPP, and when integrated with a network using differentiated services, provides MLPP-over-IP.
Broadband Satellite Routers Provide Improved Throughput
Hughes Network Systems has announced its latest generation HX broadband satellite routers, the HX260 Mesh and the HX200. These new routers provide up to twice the throughput performance and build on the advanced DVB-S2/ACM bandwidth management of the highly successful HX System. Both incorporate a high performance processor and ample onboard memory to deliver carrier grade performance for business private networks, cellular backhaul, and a wide range of broadband applications. The HX260 features an integrated, multichannel TDMA demodulator, enabling simultaneous mesh and star mode connectivity within the HX System—ideal for cost-effective private networks providing a mix of voice and data services, and easily managed from one central NOC location. The HX200 supports connection to a variety of radios, including industry-standard L-Band BUCs, and is easily configured to support the full range of advanced features offered by the HX System, including mobility support. The HX260 multichannel demodulator enables the unit to operate in full mesh mode with a single satellite hop to connect to another HX260 terminal, offering maximum network flexibility and reliability. ♦
