System and method for providing sub-band whitening in the presence of partial-band interference

Abstract

The present invention provides a method and system for providing sub-band whitening. According to one embodiment, a method estimates an interference whitening (IW) factor based on a legacy long training field (LLTF) signal, updates the estimated IW factor during transmission of data symbols, and scales the data symbols based on the updated IW factor and the estimated IW factor.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application is based upon and claims the benefit of priority of U.S. Provisional Patent Application Serial No. 62 / 883,862 filed in the U.S. Patent and Trademark Office on August 7, 2019, the entire contents of which are incorporated herein by reference. Technical Field

[0003] The present disclosure relates generally to wireless communication systems. In particular, the present disclosure relates to a system and method for providing sub-band whitening in the presence of partial-band interference. Background Art

[0004] In Wi-Fi communication systems, due to contention-based transmission opportunities, interference may be strong for some packets. In the Institute of Electrical and Electronics Engineer (IEEE) 802.11ac standard and the IEEE 802.11ax standard, the transmission bandwidth can be 80 megahertz (MHz) and 160 MHz. In the case of overlapping basic service sets (BSS) (overlapping BSS, OBSS), there may be partial band interference for broadband (e.g., 40 / 80 / 160 MHz), which affects one or more available 20 MHz sub-bands and may therefore cause severe performance degradation. Summary of the invention

[0005] According to one embodiment, a method includes estimating an interference whitening (IW) factor based on a legacy-long training field (LLTF) signal, updating the estimated IW factor during data symbol transmission, and scaling the data symbols based on the updated IW factor and the estimated IW factor.

[0006] According to one embodiment, a system includes a transceiver, a memory, and a processor configured to estimate an interference whitening (IW) factor based on a legacy long training field (LLTF) signal, update the estimated IW factor during transmission of data symbols, and scale the data symbols based on the updated IW factor and the estimated IW factor. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] The above and other aspects, features and advantages of certain embodiments of the present disclosure will become more apparent from the following detailed description in conjunction with the accompanying drawings, in which:

[0008] Figure 1A diagram showing a signal structure including an interfering signal according to one embodiment;

[0009] Figure 2A A diagram showing a system for providing sub-band whitening in the presence of partial-band interference according to one embodiment;

[0010] Figure 2B A diagram showing a system for providing sub-band whitening in the presence of partial-band interference according to one embodiment;

[0011] Figure 3 A flow chart showing a method for providing sub-band whitening in the presence of partial-band interference according to one embodiment;

[0012] Figure 4 A diagram showing a system for estimating noise and interference power (NIVar) in the time domain according to one embodiment;

[0013] Figure 5 A diagram showing a system for estimating NIVar in the frequency domain according to one embodiment;

[0014] Figure 6 A diagram showing a system for performing NIVar estimation from data according to one embodiment; and

[0015] Figure 7 A block diagram of an electronic device in a network environment according to one embodiment is shown. DETAILED DESCRIPTION

[0016] Hereinafter, embodiments of the present disclosure are described in detail with reference to the accompanying drawings. It should be noted that the same elements will be represented by the same reference numerals, although they are shown in different drawings. In the following description, specific details such as detailed configurations and components are provided only to help fully understand the embodiments of the present disclosure. Therefore, it is obvious to those skilled in the art that various changes and modifications may be made to the embodiments described herein without departing from the scope of the present disclosure. In addition, for clarity and conciseness, descriptions of well-known functions and structures are omitted. The terms described below are defined in consideration of the functions in the present disclosure, and may vary according to the user, the user's intention or custom. Therefore, the definition of the terms should be determined according to the content of this specification.

[0017] The present disclosure may have various modifications and various embodiments, wherein the embodiments will be described in detail below with reference to the accompanying drawings. However, it should be understood that the present disclosure is not limited to the embodiments, but includes all modifications, equivalents and substitutes within the scope of the present disclosure.

[0018] Although terms including ordinal numbers such as first and second can be used to describe various elements, structural elements are not limited by these terms. These terms are only used to distinguish one element from another element. For example, without departing from the scope of the present disclosure, the first structural element can be referred to as the second structural element. Similarly, the second structural element can also be referred to as the first structural element. As used herein, the term "and / or" includes any and all combinations of one or more related items.

[0019] The terms used herein are only used to describe various embodiments of the present disclosure, and are not used to limit the present disclosure. The singular form is intended to include the plural form, unless the context clearly indicates otherwise. In the present disclosure, it should be understood that the term "including" or "having" represents the presence of a feature, quantity, step, operation, structural element, component or a combination thereof, and does not exclude the possibility of the presence or addition of one or more other features, quantities, steps, operations, structural elements, components or a combination thereof.

[0020] Unless otherwise defined, all terms used herein have the same meaning as understood by those skilled in the art to which the present disclosure belongs. Terms such as those defined in general dictionaries will be interpreted as having the same meaning as the contextual meaning in the relevant art, and will not be interpreted as having an ideal or overly formal meaning unless explicitly defined in the present disclosure.

[0021] The electronic device according to one embodiment may be one of various types of electronic devices. The electronic device may include, for example, a portable communication device (e.g., a smart phone), a computer, a portable multimedia device, a portable medical device, a camera, a wearable device, or a household appliance. According to one embodiment of the present disclosure, the electronic device is not limited to those described above.

[0022] The terms used in this disclosure are not intended to limit the disclosure, but are intended to include various variations, equivalents or substitutes of the corresponding embodiments. With regard to the description of the accompanying drawings, similar reference numerals may be used to refer to similar or related elements. The singular form of the noun corresponding to an item may include one or more things, unless the relevant context clearly indicates otherwise. As used herein, each of the phrases such as "A or B", "at least one of A and B", "at least one of A or B", "A, B or C", "at least one of A, B and C" and "at least one of A, B or C" may be included in all possible combinations of the items listed together in a corresponding phrase. As used herein, terms such as "1st", "2nd", "first" and "second" may be used to distinguish a corresponding component from another component, but are not intended to limit the component to other aspects (e.g., importance or order). If an element (for example, a first element) is referred to as being “coupled”, “coupled to”, “connected to” or “connected to” another element (for example, a second element), whether or not there is the term “operably” or “communicatively”, it is intended to mean that the element can be coupled to the other element directly (for example, by wire), wirelessly or via a third element.

[0023] As used herein, the term "module" may include a unit implemented in hardware, software, or firmware, and may be used interchangeably with other terms, such as "logic," "logic block," "component," and "circuit." A module may be a single integral component, or a minimum unit or portion thereof, suitable for performing one or more functions. For example, according to one embodiment, a module may be implemented in the form of an application specific integrated circuit (ASIC).

[0024] Figure 1 A diagram of a signal structure including an interference signal according to one embodiment is shown. As shown, data packet 102 may include data sub-bands 104, 106, 108, and 110. As shown, interference signal 112 interferes with data sub-band 104, and interference signal 112 may start and end at any portion of data packet 102.

[0025] To mitigate signal degradation due to part-band interference, the present systems and methods provide frequency domain based signal whitening (scaling) based on an interference whitening (IW) factor estimated based on an estimated noise and interference variance (NIVar) (e.g., every 20 MHz sub-band).

[0026] Wi-Fi packets can be divided into two parts, the preamble and the data. The preamble starts with the legacy long training field (LLTF) that provides an estimate. The data follows the preamble.

[0027] Figure 2A A diagram of a system for providing sub-band whitening in the presence of partial band interference according to one embodiment is shown. The system 200 receives an initial signal y(i,n) for processing at a NIVar estimation block 202. The initial signal may be in the time domain or the frequency domain. The system includes a NIVar estimation block 204 based on LLTF and a NIVar estimation block 206 based on data, details of which will be referred to in Figure 3-Figure 6 Description. The system also processes the initial signal y(i,n) by a frequency and timing correction block 208 to correct the carrier frequency offset and provides a received signal starting from the first sample of the valid detected WiFi preamble at the block output. The cyclic prefix of each OFDM symbol is then discarded by a cyclic prefix (CP) removal block 210. The FFT block 212 is used to obtain a frequency domain signal for each OFDM symbol. The system 200 also includes a channel estimation block 214 to obtain an estimate of the channel experienced by the received signal. In addition, a symbol detector 216 is used to obtain an estimate of the log-likelihood ratio (LLR) of the available bits for each data symbol. Then, a hard decision block 218 determines whether each LLR corresponds to a 0-value bit or a 1-value bit. The bits obtained from the hard decision block are fed to a symbol mapper 220 to regenerate an estimate of the transmitted data symbol to be used for noise and interference power estimation during data portion reception. Mixer 215 scales the data symbols output by FFT block 212, and mixer 217 scales the channel output from channel estimation block 214. System 200 processes the output of NIVar estimation from LLTF block 204 and the output of NIVar estimation from data block 206, where both outputs are fed to NIVar estimate combiner block 221, followed by a per subband scale calculation block 222, which performs the task of updating the IW factor using the NIVar estimates obtained from L-LTF and from data, by using a first order low pass filter to smooth the estimate over time.

[0028] Figure 2B A diagram of a system for providing sub-band whitening in the presence of partial band interference according to one embodiment is shown. System 250 receives an initial signal y(i,n) for processing at an estimation point of NIVar estimation block 252. The initial signal may be in the time domain or the frequency domain. System 250 includes NIVar estimation block 254 based on LLTF and NIVar estimation block 256 based on data, details of which will be referred to in Figure 3-Figure 6Description. System 250 also processes the initial signal y(i,n) by frequency and timing correction block 258, cyclic prefix (CP) removal block 260, and FFT block 262. System 250 also includes channel estimation block 264, symbol detector 266, hard decision block 268, and symbol mapper 270. Mixer 263 scales the data symbols output by FFT block 262. Figure 2B In the illustrated embodiment, the data symbols are scaled at the output of the FFT block 262 and no scaling of the channel is required. The system 250 processes the output of the NIVar estimation block 254 from the LLTF and the output of the NIVar estimation block 256 from the data, where both outputs are fed to the NIVar estimation combiner block 271 followed by a per subband scaling calculation block 272 which also utilizes the scaled data symbols scaled at the mixer 263.

[0029] Figure 3 A flow chart 300 of a method for providing sub-band whitening in the presence of fractional-band interference according to one embodiment is shown. The system estimates an IW factor based on LLTF symbols at 302. The system estimates the IW factor based on NIVar estimates of the LLTF symbols.

[0030] Figure 4 A diagram of a system for estimating NIVar in the time domain is shown. An input wideband signal is separated into four 20 MHz signals 402a, 402b, 402c, and 402d, wherein the signals in each 20 MHz sub-band are frequency converted to baseband via mixers 403a, 403b, 403c, and 403d, and then low-pass filtered (LPF) at 404a, 404b, 404c, and 404d, respectively. For a BSS bandwidth of 40 / 80 MHz, two or four branches may be considered for further processing, respectively, depending on the bandwidth detection output. After the LPF, for a 40 or 80 MHz bandwidth, the signals 402a, 402b, 402c, and 402d are decimated (downsampled) by a factor of 2 or 4 at 405a, 405b, 405c, and 405d, respectively. It should be understood that the wideband signal may be separated into signals having other bandwidths without departing from the scope of the present disclosure. The system estimates the NIVar for each sub-band by sequentially processing the separated sub-band signals at the output of the band selection block 410. The NIVar for each sub-band is estimated from the same segmentation of the two LLTFs, and the system outputs an IW factor estimate 412.

[0031] Figure 5A diagram of a system for estimating NIVar in the frequency domain is shown according to one embodiment. The system 500 receives a time domain signal, performs an FFT operation at 502, and separates it into four 20 MHz signals 504a, 504b, 504c, and 504d, which are decimated at 506a, 506b, 506c, and 506d, respectively. No need for the system 500 Figure 4 LPF function. In this case, the sub-band location is well known for the LLTF frequency domain sequence. Note that the interference power may change during packet transmission because the interference packet arrival time and time span are random. Therefore, during packet transmission based on orthogonal frequency division multiplexing (OFDM) blocks, the NIVar as well as the IW factor are updated and subsequently smoothed by filtering. At the band selection block 512, the system estimates the NIVar for each sub-band by sequentially processing the separated sub-band signals. The NIVar for each sub-band is estimated based on the same segmentation of the two LLTFs, and the system outputs an IW factor estimate 514.

[0032] At 304, the system updates the estimated IW factor during data symbol transmission. Figure 6 A diagram of a system 600 for performing NIVar estimation from data according to one embodiment is shown. The system 600 includes a hard decision block 604, a modulation block 608, an amplitude square operation block 620, and a summation operation block 622. The system 600 uses three input quantities: the LLR(k) of a particular data symbol 602, the channel estimate 612 and the received signal Y(i,k) 616 in the frequency domain. The channel estimate 612 is scaled in the mixer 613 , and the received signal 616 in the frequency domain and the scaled channel estimate are summed in the accumulator 615 .

[0033] The received signal in the frequency domain of the i-th symbol is defined as equation (1):

[0034] Y(i,k)=∑ spatial streams H(k)X(i,k)+I(i,k)+N(i,k), (1)

[0035] Where k is the subcarrier index, I(i,k) is interference, and N(i,k) is noise. For each symbol, after symbol detection, the transmitted symbol can be regenerated based on LLR 602 via hard decision block 604 and modulation block 608, which produces the regenerated symbol 610. The noise and interference of this subcarrier can be estimated using equation (2).

[0036]

[0037] Assuming that the interference and noise have zero mean, the noise interference power variance of each sub-band (20MHz) can be estimated by equation (3):

[0038]

[0039] in 624 (generated using the magnitude square operation block 620 and the summation operation block 622 shown in equation (3)) is the error vector magnitude (EVM) of the ith symbol on the jth subband, and N j is the number of subcarriers in the jth subband.

[0040] Back to Figure 3 At 306, the system scales the channel and / or data symbols based on the estimated IW factor and the updated IW factor. Using the estimated noise plus interference power of each sub-band, the frequency domain signal of each sub-band can be scaled according to equation (4):

[0041]

[0042] in is the scaled frequency domain signal, S(i,j k ) is the i-th symbol and the j-th k Sub-bands (j k This means that the kth subcarrier is in the jth k The frequency domain signal of each sub-band can also be scaled according to equation (5):

[0043]

[0044] where S(i,j) is the scaling factor for the subcarrier belonging to the jth subband of the i-th symbol, is the estimated EVM on the jth subband, and N d is the number of sub-bands detected.

[0045] The scaling factor can be normalized on the maximum scaling factor instead of normalizing on the average scaling factor. Therefore, the scaling factor can be rewritten as equation (6).

[0046]

[0047] Normalizing by the maximum value will set the maximum value of the resulting normalization factor to 1 and will not change the dynamic range of the data as it would if you chose to normalize by the mean.

[0048] Figure 7FIG. 1 is a block diagram of an electronic device 701 in a network environment 700 according to an embodiment. Figure 7 , the electronic device 701 in the network environment 700 may communicate with the electronic device 702 via the first network 798 (e.g., a short-range wireless communication network), or communicate with the electronic device 704 or the server 708 via the second network 799 (e.g., a long-range wireless communication network). The electronic device 701 may communicate with the electronic device 704 via the server 708. The electronic device 701 may include a processor 720, a memory 730, an input device 750, a sound output device 755, a display device 760, an audio module 770, a sensor module 776, an interface 777, a tactile module 779, a camera module 780, a power management module 788, a battery 789, a communication module 790, a subscriber identification module (SIM) 796, or an antenna module 797. In one embodiment, at least one component (e.g., the display device 760 or the camera module 780) may be omitted from the electronic device 701, or one or more other components may be added to the electronic device 701. In one embodiment, some components may be implemented as a single integrated circuit (IC). For example, the sensor module 776 (eg, a fingerprint sensor, an iris sensor, or an illumination sensor) may be embedded in the display device 760 (eg, a display).

[0049] The processor 720 may execute, for example, software (e.g., program 740) to control at least one other component (e.g., hardware or software component) of the electronic device 701 coupled to the processor 720, and may perform various data processing or calculations. As at least part of the data processing or calculation, the processor 720 may load a command or data received from another component (e.g., sensor module 776 or communication module 790) into the volatile memory 732, process the command or data stored in the volatile memory 732, and store the resultant data in the non-volatile memory 734. The processor 720 may include a main processor 721 (e.g., a central processing unit (CPU) or an application processor (AP)) and an auxiliary processor 723 (e.g., a graphics processing unit (GPU), an image signal processor (ISP), a sensor hub processor, or a communication processor (CP)), and the auxiliary processor 723 may operate independently of the main processor 721 or in conjunction with the main processor 721. Additionally or alternatively, the auxiliary processor 723 may be adapted to consume less power than the main processor 721, or to perform a specific function. The auxiliary processor 723 may be implemented independently from the main processor 721 or as a part of the main processor 721 .

[0050] When the main processor 721 is in an inactive (e.g., sleep) state, the auxiliary processor 723 may control at least some functions or states related to at least one component (e.g., display device 760, sensor module 776, or communication module 790) among the components of the electronic device 701 instead of the main processor 721, or control together with the main processor 721 when the main processor 721 is in an active state (e.g., executing an application). According to one embodiment, the auxiliary processor 723 (e.g., an image signal processor or a communication processor) may be implemented as a part of another component (e.g., a camera module 780 or a communication module 790) that is functionally related to the auxiliary processor 723.

[0051] The memory 730 may store various data used by at least one component of the electronic device 701 (e.g., the processor 720 or the sensor module 776). The various data may include, for example, input data or output data of software (e.g., program 740) and commands related thereto. The memory 730 may include a volatile memory 732 or a non-volatile memory 734.

[0052] The program 740 may be stored as software in the memory 730 , and may include, for example, an operating system (OS) 742 , middleware 744 , or an application 746 .

[0053] The input device 750 may receive commands or data from outside the electronic device 701 (eg, a user) to be used by other components (eg, the processor 720) of the electronic device 701. The input device 750 may include, for example, a microphone, a mouse, or a keyboard.

[0054] The sound output device 755 can output sound signals to the outside of the electronic device 701. The sound output device 755 may include, for example, a speaker or a receiver. The speaker can be used for general purposes, such as playing multimedia or recording, and the receiver can be used to receive incoming calls. According to one embodiment, the receiver can be implemented as being separated from the speaker or being a part of the speaker.

[0055] The display device 760 can visually provide information to the outside of the electronic device 701 (e.g., a user). The display device 760 may include, for example, a display, a holographic device, or a projector, and a control circuit for controlling a corresponding one of the display, the holographic device, and the projector. According to one embodiment, the display device 760 may include a touch circuit suitable for detecting a touch, or a sensor circuit (e.g., a pressure sensor) suitable for measuring the strength of the force caused by the touch.

[0056] The audio module 770 can convert sound into an electrical signal, and vice versa. According to one embodiment, the audio module 770 can obtain sound via the input device 750, or output sound via the sound output device 755 or the earphone of the external electronic device 702 directly (e.g., wired) or wirelessly coupled to the electronic device 701.

[0057] The sensor module 776 can detect the operating state (e.g., power or temperature) of the electronic device 701 or the environmental state (e.g., the state of the user) outside the electronic device 701, and then generate an electrical signal or data value corresponding to the detected state. The sensor module 776 may include, for example, a gesture sensor, a gyroscope sensor, an atmospheric pressure sensor, a magnetic sensor, an acceleration sensor, a grip sensor, a proximity sensor, a color sensor, an infrared (IR) sensor, a biosensor, a temperature sensor, a humidity sensor, or an illumination sensor.

[0058] The interface 777 may support one or more designated protocols for the electronic device 701 to be directly (e.g., wired) or wirelessly coupled to the external electronic device 702. According to one embodiment, the interface 777 may include, for example, a high-definition multimedia interface (HDMI), a universal serial bus (USB) interface, a secure digital (SD) card interface, or an audio interface.

[0059] The connection terminal 778 may include a connector via which the electronic device 701 may be physically connected to the external electronic device 702. According to one embodiment, the connection terminal 778 may include, for example, an HDMI connector, a USB connector, an SD card connector, or an audio connector (eg, a headphone connector).

[0060] The haptic module 779 may convert an electrical signal into a mechanical stimulus (eg, vibration or motion) or an electrical stimulus, which may be recognized by a user via a sense of touch or kinesthetic sense. According to one embodiment, the haptic module 779 may include, for example, a motor, a piezoelectric element, or an electrical stimulator.

[0061] The camera module 780 may capture still images or moving images. According to one embodiment, the camera module 780 may include one or more lenses, image sensors, image signal processors, or flashes.

[0062] The power management module 788 may manage power supplied to the electronic device 701. The power management module 788 may be implemented as, for example, at least a portion of a power management integrated circuit (PMIC).

[0063] The battery 789 may supply power to at least one component of the electronic device 701. According to one embodiment, the battery 789 may include, for example, a non-rechargeable primary battery, a rechargeable secondary battery, or a fuel cell.

[0064] The communication module 790 may support establishing a direct (e.g., wired) communication channel or a wireless communication channel between the electronic device 701 and an external electronic device (e.g., electronic device 702, electronic device 704, or server 708), and perform communication via the established communication channel. The communication module 790 may include one or more communication processors that operate independently of the processor 720 (e.g., AP) and support direct (e.g., wired) communication or wireless communication. According to one embodiment, the communication module 790 may include a wireless communication module 792 (e.g., a cellular communication module, a short-range wireless communication module, or a global navigation satellite system (GNSS) communication module) or a wired communication module 794 (e.g., a local area network (LAN) communication module or a power line communication (PLC) module). A corresponding one of these communication modules can communicate with an external electronic device via a first network 798 (e.g., a short-range communication network such as Bluetooth, Wireless Fidelity (Wi-Fi) Direct, or Infrared Data Association (IrDA) standards) or a second network 799 (e.g., a long-range communication network such as a cellular network, the Internet, or a computer network (e.g., a LAN or a wide area network (WAN)). These different types of communication modules can be implemented as a single component (e.g., a single IC), or can be implemented as multiple components separated from each other (e.g., multiple ICs). The wireless communication module 792 can use the subscriber information (e.g., International Mobile Subscriber Identity (IMSI)) stored in the subscriber identification module 796 to identify and authenticate the electronic device 701 in the communication network (e.g., the first network 798 or the second network 799).

[0065] The antenna module 797 may transmit a signal or power to the outside of the electronic device 701 (e.g., an external electronic device), or receive a signal or power from the outside of the electronic device 701 (e.g., an external electronic device). According to one embodiment, the antenna module 797 may include one or more antennas, and thus, for example, at least one antenna suitable for a communication scheme used in a communication network (such as the first network 798 or the second network 799) may be selected by the communication module 790 (e.g., the wireless communication module 792). Then, a signal or power may be transmitted or received between the communication module 790 and the external electronic device via the selected at least one antenna.

[0066] At least some of the above components may be coupled to each other and transmit signals (e.g., commands or data) therebetween via an inter-peripheral communication scheme (e.g., a bus, general purpose input and output (GPIO), serial peripheral interface (SPI), or mobile industry processor interface (MIPI)).

[0067] According to one embodiment, commands or data may be sent or received between the electronic device 701 and the external electronic device 704 via a server 708 coupled to the second network 799. Each of the electronic devices 702 and 704 may be a device of the same type or a different type as the electronic device 701. All or some operations to be performed at the electronic device 701 may be performed at one or more of the external electronic devices 702, 704, or 708. For example, if the electronic device 701 should automatically perform a function or service, or perform a function or service in response to a request from a user or another device, the electronic device 701 may request one or more external electronic devices to perform at least a portion of the function or service, alternatively or in addition to performing the function or service. The one or more external electronic devices receiving the request may perform at least a portion of the requested function or service, or additional functions or additional services related to the request, and transmit the result of the execution to the electronic device 701. The electronic device 701 may provide the result as at least a portion of the reply to the request with or without further processing the result. To this end, for example, cloud computing, distributed computing, or client-server computing technology may be used.

[0068] One embodiment may be implemented as software (e.g., program 740) that includes one or more instructions stored in a storage medium (e.g., internal memory 736 or external memory 738) readable by a machine (e.g., electronic device 701). For example, the processor of the electronic device 701 may call at least one of the one or more instructions stored in the storage medium and execute it with or without one or more other components under the control of the processor. Thus, the machine may be operated to perform at least one function according to at least one instruction called. The one or more instructions may include code generated by a compiler or code executable by an interpreter. The machine-readable storage medium may be provided in the form of a non-transitory storage medium. The term "non-transitory" means that the storage medium is a tangible device and does not include signals (e.g., electromagnetic waves), but the term is not used to distinguish between semi-permanent storage of data in the storage medium and temporary storage of data in the storage medium.

[0069] According to one embodiment, the method of the present disclosure may be included and provided in a computer program product. The computer program product may be traded between a seller and a buyer as a product. The computer program product may be distributed in the form of a machine-readable storage medium (e.g., a compact disc read-only memory (CD-ROM)), or may be downloaded through an application store (e.g., PlayStore). TM ) instead of online distribution (e.g., downloading or uploading), or directly between two user devices (e.g., smart phones). In the case of online distribution, at least a part of the computer program product may be temporarily generated in a machine-readable storage medium or at least temporarily stored in a machine-readable storage medium, such as a memory of a manufacturer's server, an application store's server, or a relay server.

[0070] According to one embodiment, each component (e.g., module or program) of the above-mentioned components may include a single entity or multiple entities. One or more of the above-mentioned components may be omitted, or one or more other components may be added. Alternatively or additionally, multiple components (e.g., modules or programs) may be integrated into a single component. In this case, the integrated component may still perform one or more functions of each component in the multiple components in the same or similar manner as they were performed by a corresponding one of the multiple components before integration. The operations performed by a module, program or another component may be performed sequentially, in parallel, repeatedly or heuristically, or one or more operations may be performed or omitted in a different order, or one or more other operations may be added.

[0071] Although certain embodiments of the present disclosure have been described in the detailed description of the present disclosure, the present disclosure may be modified in various forms without departing from the scope of the present disclosure. Therefore, the scope of the present disclosure should not be determined solely based on the described embodiments, but based on the attached claims and their equivalents.

Claims

1. A method for providing sub-band whitening, comprising: Estimate the interference whitening IW factor based on the traditional long training field LLTF signal; updating the estimated IW factor during data symbol transmission; and scaling the data symbols based on the updated IW factor and the estimated IW factor, The IW factor is updated based on the noise and interference power NIVar of the received signal and the symbol detection output.

2. The method according to claim 1, wherein: The IW factor is based on a noise and interference power NIVar estimate from two LLTF segments of the LLTF signal. 3 . The method of claim 1 , further comprising separating the LLTF signal into a plurality of signals.

4. The method according to claim 3, wherein: The LLTF signal is separated into four signals.

5. The method according to claim 4, wherein: Each of the four signals is in a 20 MHz sub-band.

6. The method according to claim 1, wherein: Estimating the IW factor includes determining the error vector magnitude EVM.

7. The method according to claim 6, wherein: The EVM is determined based on the channel estimate and the data signal.

8. The method of claim 1, further comprising scaling the channel, wherein: Scaling the channel is performed based on an IW factor determined based on an error vector magnitude EVM.

9. The method of claim 1, further comprising scaling the channel, wherein: Scaling the channels is performed based on the normalization of the IW factors.

10. A system for providing sub-band whitening, comprising: Transceiver; Memory; and A processor configured to: Based on the traditional long training field LLTF signal estimation interference whitening IW factor, updating the estimated IW factor during data symbol transmission; and The data symbol is scaled based on the updated IW factor and the estimated IW factor, wherein the IW factor is updated based on noise and interference power NIVar of a received signal and a symbol detection output.

11. The system according to claim 10, wherein: The IW factor is based on a noise and interference power NIVar estimate from two LLTF segments of the LLTF signal.

12. The system according to claim 10, wherein: The processor is also configured to separate the LLTF signal into a plurality of signals.

13. The system according to claim 12, wherein: The LLTF signal is separated into four signals.

14. The system according to claim 13, wherein: Each of the four signals is in a 20 MHz sub-band.

15. The system according to claim 10, wherein: The processor is further configured to estimate the IW factor by determining an error vector magnitude (EVM).

16. The system of claim 15, wherein: The EVM is determined based on the channel estimate and the data signal.

17. The system according to claim 10, wherein: The processor is further configured to scale the channel based on an IW factor determined based on an error vector magnitude (EVM).

18. The system of claim 10, wherein: The processor is further configured to scale the channel based on normalization of the IW factor.

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