Overview

Satellite communications networks are expanding and improving in coverage, reliability, redundancy, bandwidth, and latency. These networks handle diverse traffic, ranging from commercial internet services to mission-critical voice and data communications. To ensure optimal performance, satellite networks must be monitored for voice quality, throughput, latency, packet loss, and other key metrics. Tests should be conducted end-to-end to verify the entire network path.

GL offers test solutions for monitoring satellite networks, regardless of the type of traffic. With both portable and rack-mountable equipment, GL provides versatile tools for different testing environments. Portable equipment is ideal for measuring satellite coverage in remote areas.

Rack-mountable devices can be permanently installed at ground stations, where signals are converted from wired to wireless and sent into space. These solutions can emulate traffic across satellite networks and measure user experience, such as voice and video quality, as well as fundamental packet metrics like throughput, packet loss, and jitter.

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Voice Testing over Satellite Networks

Voice Quality Testing of Radios over Satellite

Satellite communications networks handle diverse traffic, from commercial internet to mission critical communications. Unfortunately, satellite networks are prone to numerous network impairments, such as reduced bandwidth, long latency, packet loss and jitter. These impairments affect user experience, especially for voice traffic or other streaming services. Poor voice quality impacts government and military operations as well as private internet use.

GL’s test tools assess user experience over the satellite network. Key metrics include Voice Quality scores (Mean Opinion Score), measuring delay, and detecting dropouts. GL’s equipment connects with endpoint devices like satellite phones and radios, allowing for detailed monitoring and analysis of satellite networks.

These tools capture key performance indicators to evaluate the quality and reliability of communications. For Voice Quality Testing, the latest industry standard algorithms are supported, including POLQA (per ITU-T P.863) and PESQ (per ITU-T P.862).

Voice Quality Testing of Satellite Phones

With GL’s vMobile™, users can send and receive voice and data traffic over satellite networks. This handheld device connects to satellite phones and radios via Bluetooth® or wired connections. vMobile™ manages call functions, such as placing and answering calls, sending, and receiving audio, and disconnecting calls. The vMobile™ records audio from the satellite network and sends the file to WebViewer™, a central database, for voice quality analysis.

WebViewer™ offers a web-based dashboard for easy access to results. vMobile™ can also store files locally for later upload if needed. Multiple vMobile™ devices can connect to the same WebViewer™. Furthermore, multiple users can simultaneously connect to WebViewer™ to execute tests and view results. Results are displayed on Google Maps for location-based analysis and identifying areas of poor voice and data quality.

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Traffic Generation over Satellite Networks

Users can generate traffic over satellite networks using PacketExpert™ 10GX and measure the subsequent throughput, round-trip delay, packet loss, jitter, and more. Using the Multi-Stream UDP/TCP Traffic Generator and Analyzer feature, the PacketExpert™ 10GX can create multiple streams of traffic, such as voice, video, and data, over satellite links.

For each stream, the device measures the throughput, delay, packet loss, jitter, and other fundamental packet metrics. Satellite networks often have prioritization schemes for different traffic streams based on Class of Service (COS) or Differentiated Services Code Point (DSCP) tags in the Ethernet frame or IP header. The PacketExpert™ 10GX can test these prioritization schemes by generating streams with different protocol headers, COS and DSCP tags. Users can view real time graphs of throughput, latency (with nanosecond precision), packet loss, etc. for each stream independently.

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Satellite Network Link Emulation

All wireless networks, including satellite networks, introduce impairments into traffic streams due to environmental conditions and interference. Impairments include bandwidth reduction, excessive latency, packet loss, jitter, and bit errors. Customers often need to test their applications under emulated impairment conditions to determine degradations in user experience. GL provides WAN Network Emulation within the PacketExpert™ platform.

GL’s PacketExpert™ is a comprehensive Ethernet tester that can introduce precise impairments, such as bandwidth throttling, added latency, packet loss, packet corruption, packet duplication, and packet reordering. The impairments can be selectively applied to various traffic streams. Users can introduce impairments continuously, periodically, or manually at run time. Users can view real time graphs of throughput as well as up to the second statistics on the impaired traffic.

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Resources