Various aspects described herein relate to techniques for timing control with filtering in orthogonal frequency division multiplexing (OFDM)-based wireless communications systems. In an aspect, the method includes determining whether time-domain filtering or frequency-domain filtering is used for a transmission signal waveform, and identifying a time delay based on a determination that the time-domain filtering is used for the transmission signal waveform. The method further includes applying a timing correction based on the identified time delay. The techniques described herein may apply to different communications technologies, including 5th Generation (5G) New Radio (NR) communications technology.

A method of designing a digital filter for example for use in an FBMC/OQAM telecommunications system, with a target overlapping factor and meeting a specified signal to interference ratio is described, whereby a candidate filter design defined by an impulse response, satisfying the Nyquist criterion and having an overlapping factor higher than the target is selected, and the time and frequency coefficients of its impulse response inverted to define a new filter design; and truncating the impulse response defining said new filter design to the minimum number of coefficients achieving said specified signal to interference ratio.

Disclosed are method and apparatus for enabling multiple access in a wireless communication system that can enable ultralow latency, ultra-reliable, and high throughput services. The disclosed multiple access method includes: allocating resources for a plurality of user terminals according to space and frequency; performing a discrete Fourier transform on a transmission symbol for each unit of the space, the transmission symbol composed of a plurality of sub-symbols and configured to be transmitted according to the allocated space and frequency resources; and applying a frequency filter and a spatial filter on the Fourier transformation result, and wherein the applying of the frequency filter and the spatial filter comprises: selecting a pulse shaping filter according to an arranged position of the allocated frequency resource for each unit of the space and applying the selected pulse shaping filter on a sample representing a result of applying a Fourier transform on the sub-symbol to a frequency domain.

A method for transmitting an uplink signal by a user equipment on a carrier where multiple subbands, each having different subcarrier spacing, are multiplexed may include: generating M modulated symbols by modulating uplink data; repeating the M modulated symbols in both upper and lower frequency blocks, which are adjacent to a predetermined frequency block for the M modulated symbols and have the same size as that of the predetermined frequency block; obtaining a tapered pulse by multiplying a total of 3M modulated symbols, which are a result of the repetition, and a total of 3M windowing weight values in an element-wise manner; and transmitting the tapered pulse after performing an inverse Fourier transform, wherein the user equipment can restrict leakage power to subbands unsynchronized with its operating subband to be equal to or lower than a threshold by adjusting a tapering length of the tapered pulse.

A method of a user equipment (UE) in a wireless communication system is provided, the method comprises receiving, from a base station (BS), configuration information including a number of total beam quantities (N) and a number of selected beam quantities (L), wherein LN; calculating an index indicating L selected beam quantities out of N total beam quantities based on the configuration information and a predefined mapping table including combinatorial binomial coefficient values,

[00001]$C\left(x,y\right)=\left(\begin{array}{c}x\\ y\end{array}\right)$

(i.e., x choose y); and transmitting, to the BS, the index indicating the L selected beam quantities.

Different filtered-orthogonal frequency division multiplexing (f-OFDM) frame formats may be used to achieve the spectrum flexibility. F-OFDM waveforms are generated by applying a pulse shaping digital filter to an orthogonal frequency division multiplexed (OFDM) signal. Different frame formats may be used to carry different traffic types as well as to adapt to characteristics of the channel, transmitter, receiver, or serving cell. The different frame formats may utilize different sub-carrier (SC) spacings and/or cyclic prefix (CP) lengths. In some embodiments, the different frame formats also utilize different symbol durations and/or transmission time interval (TTI) lengths.

A transmitter using a channel aggregation in which available channels existing in various frequency bands are bound and transmitted and using an Orthogonal Frequency Division Multiplexing (OFDM), an Orthogonal Frequency Division Multiple Access (OFDMA), or a system similar to them as a modulation system. One or a plurality of transmission units are provided in parallel, and one or a plurality of transmission processing units are provided in parallel. The transmission processing unit has an inverse fast Fourier transforming circuit or a discrete inverse Fourier transforming circuit, a GI and overlap margin (OM) insertion circuit, and a time-domain windowing processing unit. The time-domain windowing processing unit multiplies a universal time-domain window function in accordance with a spectrum mask and transport electric power which are required in each channel, thereby suppressing out-of-band radiation electric power every channel. A kind and a window transition duration of the time-domain window function can be arbitrarily set every channel.

Various disclosed embodiments include methods and systems for communication in a wireless communication system. A method comprises receiving a signal corresponding to a plurality of modulated signals, each of the plurality of modulated signals corresponding to a unique electronic device. The method comprises filtering the received signal with a plurality of filters, each of which is matched to a corresponding filter in a respective electronic device to obtain a filtered signal for the respective electronic device. The method comprises performing a fast Fourier transform (FFT) operation on the filtered signal to obtain demodulated data corresponding to the respective electronic device.

The present application relates to a filtering scheme with low complexity. The method includes: dividing an orthogonal frequency division multiplexing (OFDM) signal into a first sideband signal, a first signal, and a second sideband signal; sampling the first sideband signal by using a first sampling rate; sampling the first signal by using a second sampling rate; sampling the second sideband signal by using a third sampling rate; and separately performing filtering processing of a third spectral mask, upsampling processing, and digital frequency conversion processing to generate a first filtered-OFDM (f-OFDM) signal, a second f-OFDM signal and a third f-OFDM signal; and superposing the first f-OFDM signal, the second f-OFDM signal, and the third f-OFDM signal to obtain an f-OFDM signal, where the first sampling rate and the third sampling rate are both less than the second sampling rate.

A broadcast TV signal is a DVB-T2 based system. A DVB-T2 transmitter checks OFDM symbols before transmission to determine a level of adjacent channel interference (ACI). If the of level of ACI is too high, i.e., above a threshold value, the OFDM symbols are filtered before transmission. Otherwise, the OFDM symbols are transmitted without filtering. A filtering field is added to an LI pre-signaling table of the broadcast DVB-T2 signal to signal a DVB-T2 receiver when the received OFDM symbols have been filtered.