Filtering-based signal transmission and receiving methods and corresponding transmitter and receiver

A communication method based on signal adjustment, the communication method comprising:

• receiving system information including a bandwidth corresponding to each of at least one sub-band;
• determining, by a terminal, a length of a cyclic prefix and a length of a cyclic postfix corresponding to a respective sub-band, based on the bandwidth included in the received system information;
• receiving, from a base station, information notifying adjustment amount of the length of the cyclic prefix and the length of the cyclic postfix;
• adjusting the determined length of the cyclic prefix and the determined length of the cyclic postfix based on the received information;
• and
• performing communication with the base station using signals with the adjusted length of the cyclic prefix and the adjusted length of the cyclic postfix from the respective sub-band,
• wherein the adjustment amount is related to a power relationship between carrier modulated symbols adjacent to each other, the carrier modulated symbols corresponding to at least one carrier modulated signal, and
• wherein, in response to the carrier modulated symbols adjacent to each other having different power, low-power symbols adjacent to high-power symbols, based on the adjusting, use a different ratio of the length of the cyclic prefix to the length of the cyclic postfix.

A method for filtering a signal, the method comprising:

• performing, by a receiver, time-domain matched filtering on each received signal, corresponding to at least one sub-band;
• removing, by the receiver, a cyclic prefix and a cyclic postfix from the filtered signal from the at least one sub-band, and performing carrier demodulation, respectively;
• and
• detecting and estimating, by the receiver, the demodulated signal from the at least one sub-band,
• wherein a length of the cyclic prefix and a length of the cyclic postfix corresponding to a respective sub-band are determined based on a bandwidth of the respective sub-band,
• wherein the length of the cyclic prefix and the length of the cyclic postfix are adjusted based on information, received from a transmitter, notifying adjustment amount of the length of the cyclic prefix and the length of the cyclic postfix,
• wherein the adjustment amount is related to a power relationship between carrier modulated symbols adjacent to each other, the carrier modulated symbols corresponding to at least one carrier modulated signal, and
• wherein, in response to the carrier modulated symbols adjacent to each other having different power, low-power symbols adjacent to high-power symbols, based on the adjusting, use a different ratio of the length of the cyclic prefix to the length of the cyclic postfix.

A method for signal adjustment, the method comprising:

• transmitting, by a base station, system information including length information of a cyclic prefix and a cyclic postfix corresponding to a respective sub-band;
• and
• performing, by the base station, communication with a terminal using at least one signal with the cyclic prefix and the cyclic postfix corresponding to the respective sub-band,
• wherein the length information is determined based on a bandwidth corresponding to the respective sub-band,
• wherein a length of the cyclic prefix and a length of the cyclic postfix are adjusted according to a power relationship between carrier modulated symbols adjacent to each other, the at least one signal being mapped to the carrier modulated symbols, and
• wherein, in response to the carrier modulated symbols adjacent to each other having different power, low-power symbols adjacent to high-power symbols, based on the adjusting, use a different ratio of the length of the cyclic prefix to the length of the cyclic postfix.

A filtering-based transmitter comprising:

• a carrier modulator configured to:
• perform carrier modulation on at least one signal from each of at least one sub-band,
• add a cyclic prefix and a cyclic postfix to the at least one carrier modulated signal, respectively, a length of the cyclic prefix and a length of the cyclic postfix corresponding to a respective sub-band being determined based on a bandwidth of the respective sub-band, and
• adjust the length of the cyclic prefix and the length of the cyclic postfix according to a power relationship between carrier modulated symbols adjacent to each other, the carrier modulated symbols corresponding to the at least one carrier modulated signal;
• a filter configured to perform time-domain filtering on the carrier modulated signal which is added with the cyclic prefix and the cyclic postfix, from the respective sub-band;
• and
• a transmitter configured to transmit the filtered signal from the at least one sub-band,
• wherein, in response to the carrier modulated symbols adjacent to each other having different power, low-power symbols adjacent to high-power symbols, based on the adjusting, use a different ratio of the length of the cyclic prefix to the length of the cyclic postfix.

A filtering-based receiver comprising:

• a matched filter configured to perform time-domain matched filtering on each received signal, corresponding to at least one sub-band;
• a carrier demodulator configured to remove a cyclic prefix and a cyclic postfix from the filtered signal from the at least one sub-band, and perform carrier demodulation, respectively;
• and
• an estimation device, configured to detect and estimate the demodulated signal from the at least one sub-band,
• wherein a length of the cyclic prefix and a length of the cyclic postfix corresponding to a respective sub-band are determined based on a bandwidth of the respective sub-band,
• wherein the length of the cyclic prefix and the length of the cyclic postfix are adjusted based on information, received from a filtering-based transmitter, notifying adjustment amount of the length of the cyclic prefix and the length of the cyclic postfix,
• wherein the adjustment amount is related to a power relationship between carrier modulated symbols adjacent to each other, the carrier modulated symbols corresponding to at least one carrier modulated signal, and
• wherein, in response to the carrier modulated symbols adjacent to each other having different power, low-power symbols adjacent to high-power symbols, based on the adjusting, use a different ratio of the length of the cyclic prefix to the length of the cyclic postfix.

A method by a transmitter in a terminal, the method comprising:

• performing carrier modulation for at least one signal from each of at least one sub-band;
• adding a transmission cyclic prefix and a transmission cyclic postfix to the at least one carrier modulated signal, respectively, a length of the transmission cyclic prefix and a length of the transmission cyclic postfix corresponding to a respective sub-band being determined based on a bandwidth of the respective sub-band;
• adjusting the length of the transmission cyclic prefix and the length of the transmission cyclic postfix according to a power relationship between carrier modulated symbols adjacent to each other, the carrier modulated symbols corresponding to the at least one carrier modulated signal;
• after the adding of the transmission cyclic prefix and transmission cyclic postfix, filtering each carrier modulated signal in a time domain;
• and
• transmitting, by the transmitter, the filtered signal from the at least one sub-band,
• wherein, in response to the carrier modulated symbols adjacent to each other having different power, low-power symbols adjacent to high-power symbols, based on the adjusting, use a different ratio of the length of the cyclic prefix to the length of the cyclic postfix.