Filter apparatus, multiplex device and associated method

摘要

It is presented a filter apparatus comprising: a first frequency shifter arranged to accept an input signal of the apparatus; a first filter; a second frequency shifter; a second filter; and a third frequency shifter, the output of which is connected to the output of the apparatus. The first frequency shifter, the first filter, the second frequency shifter, the second filter and the third frequency shifter are serially connected; and each one of the first frequency shifter, second frequency shifter and third frequency shifter has separate shift input signals, respectively. A corresponding radio base station assembly and method are also presented.

主权项

1. A multiplex device comprising:
at least first and second filter apparatuses configured to provide respective filtered signals at non-overlapping frequency bands on respective outputs thereof, each of the first and second filter apparatuses comprising:
a first frequency shifter configured to accept an input signal of the corresponding filter apparatus;a first filter with an input from the first frequency shifter;a second frequency shifter with an input from the first filter;a second filter with an input from the second frequency shifter;a third frequency shifter with an input from the second filter and having an output connected to the output of the corresponding apparatus;wherein one of the first and the second filters blocks frequencies below a lower cut-off frequency, and the other of the first and the second filters blocks frequencies above an upper cut-off frequency;wherein the first frequency shifter, the first filter, the second frequency shifter, the second filter, and the third frequency shifter are connected in a sequential series;wherein the first, second, and third frequency shifters have respective separate shift input signals;wherein the bandwidth of the respective filtered signal is configurable by adjustment of the shift input signal to the first frequency shifter and by adjustment of the shift input signal to the second frequency shifter; a first combiner device comprising:
a first combiner input connected to the output of the first filter apparatus;a second combiner input connected to the output of the second filter apparatus;a combiner output operative to provide an output signal which is a combination of signals provided on the first and second combiner inputs.