Specifications

DMD20/20LBST Universal Satellite Modem Theory of Operation
MN-DMD20-20LBST Revision 14 3–30
Figure 3-12. Same Link Using Radyne DMD20 and DoubleTalk
Carrier-in-Carrier
Traditional Full Duplex Link Duplex Link with DoubleTalk Carrier-in-
Carrier
Figure 3-13. Duplex Link Optimization
Because acquiring the delay and frequency offset of the interfering carrier is fundamentally a
correlation operation, anything deterministic in the interfering carrier (within the correlation
window of the algorithm) will potentially produce false correlation peaks and result in incorrect
delays and/or frequency. Normally, this is not a problem, since energy dispersal techniques are
utilized in the vast majority of commercial and military modems. However, it is something that
must be kept in mind when troubleshooting a system that utilizes the DoubleTalk Carrier-in-
Carrier technique for signal suppression.
CDM
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625 with CnC
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DMD20 with CnC
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DMD20 with CnC