QFlex-400  Dual IF/L-Band Satellite Modem


The QFlex-400™ software-defined satellite modem, a variant of our flagship Q-Flex™, is our highest data rate modem. Compared to the standard Q-Flex™, it supports much higher data rates, an extended frequency range, better RF performance, improved carrier cancellation, more headroom for future upgrades and lower power consumption.

It is ideal as a versatile point-to-point network modem or a remote modem in a point-to- multipoint network. It is fully compatible with our Q-NET™ satellite network solution and is a drop-in replacement for the Q-Flex™/Q-Lite™.



  • Dual IF/L-band; data rates to 345Mbps
  • Low power consumption, typically 30W
  • XStream IP™ advanced IP optimization suite, including TCP & HTTP acceleration, header & payload compression, dynamic routing, traffic shaping, jitter reduction, en- cryption & ACM
  • DVB-S2/S2X & FastLink™ LDPC
  • Optimized spectral roll-offs, including 5%
  • Paired Carrier+™ enhanced carrier overlay
  • LinkGuard™ signal-under-carrier interference detection
  • Built-in spectrum & constellation monitors
  • DVB Carrier ID (to DVB-CID standard)
  • Q-NET™ Navigator network control app
  • Interoperates fully with Q-Flex™ & Q-Lite™
  • Software Defined Network support: vendor- independent network device control using standard commands (supports OpenFlow)



Main Specifications



L-band: 950 to 2450MHz (resolution 1Hz)

IF: 50 to 180MHz

(resolution 100Hz)

N-type connectors for Tx & Rx

Data Rate

Standard: 2,048kbps

Options: 5Mbps, 10Mbps, 25Mbps, 60Mbps, 100Mbps, 200Mbps and 345Mbps


Data Rate Limits

DVB-S2/S2X: 50kbps to 345Mbps FastLinkLDPC: 18kbps to 100Mbps 1bps resolution

TPC: 2.4kbps to 60Mbps 1bps resolution

Symbol Rate Limits

DVB-S2/S2X: 100ksps to 70Msps FastLinkLDPC: 18ksps to 40Msps TPC: 2.4ksps to 40Msps


Operating Modes

DVB-S2/S2X (EN 302 307-1 &

EN 302 307-2)

Closed Network (+ ESC) (IESS-315)

IBS/IDR (IESS-308/309/310/314) options



Return Loss

L-band: >15dB; IF: >18dB


1:1 through 1:16 redundancy