A receiver may include a first filter configured to generate a first estimation of a symbol of a received signal and a second filter configured to generate a second estimation of the symbol of the received signal. The receiver may also include a decoder configured to decode the symbol using one of the first estimation and the second estimation and a decision circuit configured to select one of the first estimation and the second estimation to provide to the decoder for decoding of the symbol based on a comparison of the first estimation to an estimation threshold.

A receiver may include a first filter configured to generate a first estimation of a symbol of a received signal and a second filter configured to generate a second estimation of the symbol of the received signal. The receiver may also include a decoder configured to decode the symbol using one of the first estimation and the second estimation and a decision circuitconfigured to select one of the first estimation and the second estimation to provide to the decoder for decoding of the symbol based on a comparison of the first estimation to an estimation threshold.

receiver may include a first filter configured to generate a first estimation of a symbol of a received signal and a second filter configured to generate a second estimation of the symbol of the received signal. The receiver may also include a decoder configured to decode the symbol using one of the first estimation and the second estimation and a decision circuit configured to select one of the first estimation and the second estimation to provide to the decoder for decoding of the symbol based on a comparison of the first estimation to an estimation threshold.

A receiver may include a first filter configured to generate a first estimation of a symbol of a received signal and a second filter configured to generate a second estimation of the symbol of the received signal. The receiver may also include a decoder configured to decode the symbol using one of the first estimation and the second estimation and a decision circuit configured to select one of the first estimation and the second estimation to provide to the decoder for decoding of the symbol based on a comparison of the first estimation to an estimation threshold.

receiver may include a first filter configured to generate a first estimation of a symbol of a received signal and a second filter configured to generate a second estimation of the symbol of the received signal. The receiver may also include a decoder configured to decode the symbol using one of the first estimation and the second estimation and a decision circuit configured to select one of the first estimation and the second estimation to provide to the decoder for decoding of the symbol based on a comparison of the first estimation to an estimation threshold.

A continuously or step variable passive noise filter for removing noise from a signal received from a DUT added by a test and measurement instrument channel. The noise filter may include, for example, a splitter splits a signal into at least a first split signal and a second split signal. A first path receives the first split signal and includes a variable attenuator and/or a variable delay line which may be set based on the channel response of the DUT which is connected. The variable attenuator and/or the variable delay line may be continuously or stepped variable, as will be discussed in more detail below. A second path is also included to receive the second split signal and a combiner combines a signal from the first path and a signal from the second path into a combined signal.

A maximum likelihood sequence estimation circuit includes: a signal extraction unit that estimates a reception sample signal including a preceding wave component and a reception sample signal including a delayed wave component from a plurality of reception sample signals sampled from a reception signal at sample intervals shorter than symbol intervals, and extracts, based on an estimation result, both first reception sample signals and second reception sample signals from the plurality of reception sample signals at the symbol intervals; and a maximum likelihood sequence estimation unit that estimates a maximum likelihood sequence using the first reception sample signals extracted and the second reception sample signals extracted.

A maximum likelihood sequence estimation circuit includes: a signal extraction unit that estimates a reception sample signal including a preceding wave component and a reception sample signal including a delayed wave component from a plurality of reception sample signals sampled from a reception signal at sample intervals shorter than symbol intervals, and extracts, based on an estimation result, both first reception sample signals and second reception sample signals from the plurality of reception sample signals at the symbol intervals; and a maximum likelihood sequence estimation unit that estimates a maximum likelihood sequence using the first reception sample signals extracted and the second reception sample signals extracted.

A continuously or step variable passive noise filter for removing noise from a signal received from a DUT added by a test and measurement instrument channel. The noise filter may include, for example, a splitter splits a signal into at least a first split signal and a second split signal. A first path receives the first split signal and includes a variable attenuator and/or a variable delay line which may be set based on the channel response of the DUT which is connected. The variable attenuator and/or the variable delay line may be continuously or stepped variable, as will be discussed in more detail below. A second path is also included to receive the second split signal and a combiner combines a signal from the first path and a signal from the second path into a combined signal.

A wireless communication method according to an embodiment includes precoding a stream of a transmission signal in a time domain by using an FIR filter, controlling a transmission power of the precoded stream, amplifying the precoded stream such that the controlled transmission power is obtained; and performing control for changing a tap length in precoding such that the tap length is decreased in a case where a magnitude of a last tap coefficient in precoding is small and the tap length is increased in a case where the magnitude is large, with respect to a threshold value calculated on the basis of quality information of a received signal fed back from a reception device that has received the amplified stream or quality information of a received signal calculated by using at least characteristics of an amplifier.