Satellite signal frequency translation and stacking
View Patent ↗An outdoor satellite receiving unit (ODU) receives several independent satellite signals, selects two signals with a switch matrix, downconverts the two signals to a bandstacked signal with a high and a low band signal, and outputs the bandstacked signal on the same cable to receiver units. Several satellite signals can be selected in groups of two or more and output to independent receiver units. Signal selecting is performed at the received radio frequency (RF) and bandstacking is performed with a single downconversion step to an intermediate frequency (IF). Channel stacking on the same cable of more than two channels from several satellites can be achieved by using frequency agile downconverters and bandpass filters prior to combining at the IF output. A slow transitioning switch minimizes signal disturbances when switching and maintains input impedance at a constant value.
1. A device for processing satellite signals comprising:
a first amplifier chain that receives a first RF signal;
a second amplifier chain that receives a second RF signal;
a first bandpass filter coupled to the output of the first amplifier chain;
a second bandpass filter coupled to the output of the second amplifier chain;
a matrix switch coupled to the outputs of the first bandpass filter and the second bandpass filter;
a frequency converter block coupled to the outputs of the matrix switch that outputs frequency converted signals;
a combiner coupled to the output of matrix switch that combines the frequency converted signals and produces a frequency stacked IF output wherein a single frequency conversion is performed between the RF input signals and the frequency stacked IF output;
a first output filter coupled to an output of the frequency converter block for selecting a first set of frequencies;
a second output filter coupled to another output of the frequency converter block for selecting a second set of frequencies wherein the outputs of first output filter and the second output filter are coupled to the inputs of the combiner.
2. A device for processing satellite signals comprising:
a first amplifier chain that receives a first RF signal;
a second amplifier chain that receives a second RF signal;
a first bandpass filter coupled to the output of the first amplifier chain;
a second bandpass filter coupled to the output of the second amplifier chain;
a matrix switch coupled to the outputs of the first bandpass filter and the second bandpass filter;
a frequency converter block coupled to the outputs of the matrix switch that outputs frequency converted signals;
a combiner coupled to the output of matrix switch that combines the frequency converted signals and produces a frequency stacked IF output wherein a single frequency conversion is performed between the RF input signals and the frequency stacked IF output;
a first output filter coupled to an output of the frequency converter block for selecting a first set of frequencies;
a second output filter coupled to another output of the frequency converter block for selecting a second set of frequencies wherein the outputs of the first output filter and the output of the second output filter are coupled to the inputs of the combiner.
3. A device for processing satellite signals comprising:
a first amplifier chain that receives a first RF signal;
a second amplifier chain that receives a second RF signal;
a first bandpass filter coupled to the output of the first amplifier chain;
a second bandpass filter coupled to the output of the second amplifier chain;
a matrix switch coupled to the outputs of the first bandpass filter and the second bandpass filter;
a frequency converter block coupled to the outputs of the matrix switch that outputs frequency converted signals;
a combiner coupled to the output of matrix switch that combines the frequency converted signals and produces a frequency stacked IF output wherein a single frequency conversion is performed between the RF input signals and the frequency stacked IF output;
a circuit for processing an external IF signal comprising:
an input for the external IF signal;
a high pass filter and a low pass filter wherein the external IF signal input is coupled to the input of both the high pass filter and the low pass filter;
the output of the high pass filter is coupled to the input of a first upconverter block; and
the output of the low pass filter is coupled to the input of a second upconverter block;
wherein the output of the first upconverter block and the second upconverter block are inputs to the matrix switch.
4. The device for processing satellite signals of claim 1 further comprising:
an input for the external IF signal;
a high pass filter and a low pass filter wherein the external IF signal input is coupled to the input of both the high pass filter and the low pass filter;
the output of the low pass filter is coupled to the input of a second upconverter block;
wherein the outputs of the first upconverter block and the second upconverter block are input to the matrix switch.
5. The device for processing satellite signals of claim 1 further comprising:
a circuit for processing an external IF signal; and
a second matrix switch coupled to the output of the frequency converter block and the output of the external IF signal processing circuit wherein the output of the second matrix switch is coupled to the inputs of both the first output filter and the second output filter.
6. A device for processing satellite signals comprising:
a first amplifier chain that receives a first RF signal and comprises means for adjusting the power level of the output of the first amplifier chain;
a second amplifier chain that receives a second RF signal and comprises means for adjusting the power level of the output of the second amplifier chain wherein the output of the first amplifier chain and the output of the second amplifier chain are substantially equal;
a first bandpass filter coupled to the output of the first amplifier chain;
a second bandpass filter coupled to the output of the second amplifier chain;
a matrix switch coupled to the outputs of the first bandpass filter and the second bandpass filter;
a frequency converter block coupled to the outputs of the matrix switch that outputs frequency converted signals; and
a combiner coupled to the output of matrix switch that combines the frequency converted signals and produces a frequency stacked IF output wherein a single frequency conversion is performed between the RF input signals and the frequency stacked IF output.
7. A device comprising:
a first amplifier chain that receives a first RF signal;
a second amplifier chain that receives a second RF signal;
a first bandpass filter coupled to the output of the first amplifier chain;
a second bandpass filter coupled to the output of the second amplifier chain;
a matrix switch coupled to the outputs of the first bandpass filter and the second bandpass filter, the matrix switch comprising signal switches wherein the transition between switch states is slowed down to allow tracking loops in a system receiving processed satellite signals to track out the signal change caused by the switching;
a frequency converter block coupled to the outputs of the matrix switch that outputs frequency converted signals;
a combiner coupled to the output of matrix switch that combines the frequency converted signals and produces a frequency stacked IF output wherein a single frequency conversion is performed between the RF input signals and the frequency stacked IF output.
8. A device comprising:
a first amplifier chain that receives a first RF signal;
a second amplifier chain that receives a second RF signal;
a first bandpass filter coupled to the output of the first amplifier chain;
a second bandpass filter coupled to the output of the second amplifier chain;
a matrix switch coupled to the outputs of the first bandpass filter and the second bandpass filter, the matrix switch comprising signal switches that maintain substantially constant input impedances and transition between switch states is slowed down to allow tracking loops in a system receiving processed satellite signals to track out the signal change caused by the switching;
a frequency converter block coupled to the outputs of the matrix switch that outputs frequency converted signals;
a combiner coupled to the output of matrix switch that combines the frequency converted signals and produces a frequency stacked IF output wherein a single frequency conversion is performed between the RF input signals and the frequency stacked IF output.