The FCC was probing allegations that its routers were not in "full compliance" with FCC regulations on power levels that prevent against adjacent-channel interference
The investigation aimed to evaluate performance of three different commercially available DVB-T receivers in the presence from strong adjacent-channel interference
of downlink LTE Frequency division duplex signal.
For links within interference range, the co-channel interference occurs from transmissions on the same channel, whereas the adjacent-channel interference
occurs from transmissions on adjacent and overlapping channels.
The techniques and hardware described are also applicable to sonar applications and adaptive digital filtering, which could reduce adjacent-channel interference
in communications systems, enabling increased use of the frequency spectrum.
The system performances are linked to adjacent-channel interference
ratio (ACIR) values.
results when varying individual channel strengths from multiple drops interfere with each other, inhibiting the ability of the modem to distinguish noise from data.
This amplitude compression causes the frequency spectrum to spread into adjacent channels, which could create an adjacent-channel interference
Other design constraints are the result of regulatory bodies, which specify power spectral density masks defining the maximum allowable adjacent-channel interference
The main objectives of any smart antenna system are reduction of ISI, removal of CCI, mitigation of adjacent-channel interference
, enhancement of spectrum efficiency, improvement of BER, reduction of outage probability, improvement of transmission efficiency and reduction of hand-off rate and crosstalk.
By integrating all the components necessary for generating accurate co- and adjacent-channel interference
conditions, the emulator provides a single instrument solution to a problem that previously required more than three instruments.
Since more users are intended to occupy adjacent channels, the potential for adjacent-channel interference
actually may be higher in spread spectrum receivers as compared to narrowband systems.
In a communication system, the IMD products appear in an adjacent channel and cause adjacent-channel interference
. These undesirable intermodulation products must be removed to levels below -60 to -70 dBc for most communication systems to minimize adjacent-channel interference