Receiver, transmitter and variable bandwidth transmission method
Solutions for receiving and transmitting variable transmission bandwidth signal are provided. A receiver comprises square-root raised cosine filter bank, each filter of the filter bank configured to filter a subband, and an adder configured to add up the output signals of one or more filters of the filter bank to obtain a sum signal, the sum of the subbands of the one or more filters being equal to the transmission bandwidth of the received signal. A transmitter comprises a transmission filter, the roll-off factor of the transmission filter being selected on the basis of the bandwidth of the signal to be transmitted.
1 . A method for receiving a variable transmission bandwidth signal, the method comprising:
filtering a received signal with one or more filters of a square-root raised cosine filter bank, each filter having a same input signal, and configured to filter a subband; and
adding up output signals of the one or more filters of the filter bank to obtain a sum signal, a sum of the subbands of the one or more filters being equal to the transmission bandwidth of the received signal and center frequencies of filters filtering adjacent subbands being orthogonal to each other.
2 . The method of claim 1 , further comprising: selecting a number of filters whose output is to be added up on the basis of the transmission bandwidth of the received signal.
3 . The method of claim 1 , further comprising: filtering the received signal with the one or more filters of a square-root raised cosine filter bank, each filter in the filter bank having a fixed bandwidth.
4 . The method of claim 1 , further comprising: measuring the bandwidth of the received signal periodically.
5 . The method of claim 1 , wherein the received signal comprises frames, and the bandwidth of the received signal is measured during each received frame.
6 . A receiver in a telecommunication system, comprising:
a square-root raised cosine filter bank, wherein each filter of the filter bank has same input signal and is configured to filter a subband; and
an adder configured to add up output signals of one or more filters of the filter bank to obtain a sum signal, a sum of the subbands of the one or more filters being equal to a transmission bandwidth of a received signal and center frequencies of filters filtering adjacent subbands being orthogonal to each other.
7 . The receiver of claim 6 , wherein the obtained sum signal has a raised cosine filter spectrum.
8 . The receiver of claim 6 , wherein a bandwidth of each filter in the filter bank is fixed.
9 . The receiver of claim 6 , wherein the receiver is configured to select a number of filters whose output is to be added in the adder on the basis of the transmission bandwidth of the received signal.
10 . A transmitter in a telecommunication system, comprising a transmission filter, wherein the transmitter is configured to select a roll-off factor of the transmission filter on the basis of a bandwidth of a signal to be transmitted.
11 . The transmitter of claim 10 , wherein the transmitter is configured to select the transmission filter on the basis of the signal to be transmitted.
12 . The transmitter of claim 10 , wherein the transmission filter is comprises:
a square-root raised cosine filter bank, wherein each filter of the filter bank has a same input signal and is configured to filter a subband; and
an adder configured to add up output signals of one or more filters of the filter bank to obtain a sum signal, a sum of the subbands of the one or more filters being equal to a transmission bandwidth of the signal to be transmitted and center frequencies of filters filtering adjacent subbands being orthogonal to each other.
13 . The transmitter of claim 10 , wherein the sum signal has a raised cosine filter spectrum.
14 . The transmitter of claim 10 , wherein a bandwidth of each filter in the filter bank is fixed.
15 . A variable transmission bandwidth receiver in a telecommunication system, comprising:
a square-root raised cosine filter bank, wherein each filter of the filter bank has a same input signal and is configured to filter a subband; and
an adder configured to add up output signals of one or more filters of the filter bank to obtain a variable transmission bandwidth sum signal having a raised cosine filter spectrum, a sum of subbands of the one or more filters being equal to a transmission bandwidth of a received signal and center frequencies of filters filtering adjacent subbands being orthogonal to each other.
16 . A base station receiver in a telecommunication system, comprising:
a square-root raised cosine filter bank, wherein each filter of the filter bank has a same input signal and is configured to filter a subband; and
an adder configured to add up output signals of one or more filters of the filter bank to obtain a sum signal, a sum of subbands of the one or more filters being equal to a transmission bandwidth of a received signal and center frequencies of filters filtering adjacent subbands being orthogonal to each other.
17 . A mobile station receiver in a telecommunication system, comprising:
a square-root raised cosine filter bank, wherein each filter of the filter bank has a same input signal and is configured to filter a subband; and
an adder configured to add up output signals of one or more filters of the filter bank to obtain a sum signal, a sum of subbands of the one or more filters being equal to a transmission bandwidth of a received signal and center frequencies of filters filtering adjacent subbands being orthogonal to each other.
18 . A base station transmitter in a telecommunication system, comprising a transmission filter, wherein the transmitter is configured to select a roll-off factor of the transmission filter on the basis of a bandwidth of a signal to be transmitted.
19 . A mobile station transmitter in a telecommunication system, comprising a transmission filter, wherein the transmitter is configured to select a roll-off factor of the transmission filter on the basis of a bandwidth of a signal to be transmitted.
20 . A method for controlling transmission of a variable transmission bandwidth signal in a transmitter, the method comprising: selecting a roll-off factor of the transmission filter of the transmitter on the basis of a bandwidth of a signal to be transmitted.
21 . The method of claim 20 , further comprising: filtering the signal to be transmitted with one or more filters of a square-root raised cosine filter bank, each filter of the filter bank having a same input signal and is configured to filter a subband; and
adding up output signals of the one or more filters of the filter bank to obtain a sum signal, a sum of the subbands of the one or more filters being equal to a transmission bandwidth of a signal and center frequencies of filters filtering adjacent subbands being orthogonal to each other.
22 . A computer program embodied within a computer readable medium, the computer program including instructions for executing a computer process for receiving a variable transmission bandwidth signal, the process comprising:
filtering a received signal with one or more filters of a square-root raised cosine filter bank, each filter having the same input signal and configured to filter a subband; and
adding up output signals of the one or more filters of the filter bank to obtain a sum signal, a sum of the subbands of the one or more filters being equal to a transmission bandwidth of the received signal and center frequencies of filters filtering adjacent subbands being orthogonal to each other.
23 . A computer program embodied within a computer medium, computer program including instructions for executing a computer process for transmitting a variable bandwidth signal in a transmitter comprising a transmission filter, the process comprising:
controlling a roll-off factor of the transmission filter on the basis of a bandwidth of a signal to be transmitted.
24 . The computer program distribution medium of claim 22 , the distribution medium including at least one of a computer readable medium, a program storage medium, a record medium, a computer readable memory, a computer readable software distribution package, a computer readable signal, a computer readable telecommunications signal, and a computer readable compressed software package.