Enhanced Bandwidth Efficient Modem. (EBEM) Cryptographic Module. Non- Proprietary Security Policy. Document Number , Rev. ViaSat will provide the Army with MD(U) strategic EBEM and This modem uses advanced modulation and coding technology to. ViaSat Inc. (Nasdaq:VSAT) demonstrated its DISA certified MD Enhanced Bandwidth Efficient Modem (EBEM) to members of the U.S.

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A digital modulator transforms a digital stream into a radio signal on Intermediate frequency IF.

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Link budget analysis can determine feasibility, link configuration, and the possible overall savings of power and bandwidth with PCMA. Articles lacking sources from October All articles lacking sources.

The technology further enhances the benefits of any advanced modulation techniques or turbo coding you may already use. Probably the best way of understanding modem’s work is to look at its internal structure. However within common networks, interoperability with efficiency is the goal.


A demodulator is one of the most important parts of the receiver. The objective is to field fewer types of wireless network devices, while providing improved modfm interoperability to accommodate the emergence of Internet Protocol IP as a connectivity standard.

The bottom line advantage of the MD efficiency is that more carriers can be placed on a single satellite transponder and those carriers can be better utilized, enabling more warfighters to gain access to more data when and where they need it.

Interoperability and an open-standard approach has great advantages, but those responsible for military SATCOM still need to be sure they choose the hardware that delivers the biggest and most efficient data pipe to the warfighter in the field. A satellite modem or satmodem is a modem used to establish data transfers using a communications satellite as a relay.


Recovering a symbol clock making a local symbol clock generator synchronous with the remote one is one of the most important tasks of a demodulator. This is achieved by the following two circuits:. A block diagram of a generic satellite modem is ebrm on the image.

The technology uses an adaptive self-interference cancellation technique to subtract the transmitted signal and recover the desired signal. Providing an open standard for this ebe forward error correction technique means that efficiency and interoperability can finally coexist.

While most satellite transmissions require separate frequencies to transmit eebm receive, ViaSat PCMA technology enables one simplex carrier to be superimposed on another carrier, potentially decreasing the bandwidth required by as much as 50 percent. Satellite data unit Satellite dish Satellite modem Satellite phone Spacebus Very-small-aperture terminal. Ebme are also industrial satellite modems intended to provide a permanent link. There are some devices that include only a demodulator and no modulator, thus only allowing data to be downloaded by satellite that are also referred to as “satellite modems.

Scrambling shouldn’t be confused moddem encryption, since it doesn’t protect information from intruders. Satellite modems are often used for home internet access. To reach that objective, DoD policy includes a reduction in the number of available wireless waveforms and corresponding network hardware. Moreover, it is possible to develop a demodulator which can process signals with different modulation types. This page was last edited on 24 Octoberat A descrambler restores the original stream from the scrambled one.

For well-groomed transponders, PCMA can be of value, but to a lesser degree. The main functions of a satellite modem are modulation and demodulation. In traditional fixed-channel military satellite communication environments, where a dB link margin is typical, these features can provide more than a percent improvement in data throughput. List of communications satellite firsts List of communication satellite companies.

A multiplexer transforms several digital streams into one stream. Interoperability does not mean that SATCOM users should be faced with only a plain vanilla set of choices for their networking, rather that those choices should meet an underlying ability to interoperate with other similar network devices. There are several modulation types such as PSK and QAM that have a phase ambiguity, that is, a carrier can be restored in different ways. By using this site, you agree to the Terms of Use and Privacy Policy.

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Satellite modem

Known turbo codes at reasonable block size and complexity can come quite close to the Shannon channel capacity limit within about 1 to 2 ebfm.

Though this new standard is often thought of as catching the military up to commercial standards and technology, the new B standard is actually enhanced beyond pure commercial technology. This module provides a basis for Ethernet interface interoperability amongst satellite modem vendors.

The primary additions to the new standard include government approved TRANSECadvanced modulation and forward error correction techniques, and enhancements specific to IP network-centric operation.

Evem Learn how and when to ebme this template message. The purpose of the analog tract in the receiver is to convert signal’s frequency, to adjust its power via an automatic gain control circuit and to get its complex envelope components.

Increased symbol rates to 60 Msps providing single carrier data rates up to Mbps. A number of features and choices remain when ebme wireless networking equipment like the satellite communications modems that form the backbone of many wireless networks.

If downlink power decreases, ITA then automatically and dynamically decreases the link data rate using more robust waveforms to maintain the link connection. This is often referred to as ‘Muxing. If the analog signal was digitized without a four-quadrant multiplier, the complex envelope has to be calculated by a digital complex mixer.