DE102013222328B4 - Channel estimation for pure phase feedback and methods for use with it - Google Patents

Abstract

An apparatus comprising: a receiver for receiving a first signal from at least one other device comprising a data frame, the data frame comprising a phase feedback request; a baseband processor coupled to the receiver generating phase feedback information; a transmitter coupled to the baseband processor that sends an acknowledgment (ACK) frame to the at least one other device in response to the data frame, the ACK frame comprising the phase feedback information.

Description

CROSS REFERENCE TO RELATED PATENTS / PATENT APPLICATIONS

1. 1. Vorläufige US-Anmeldung Nr. 61/722,279 mit dem Titel „CHANNEL ESTIMATION FOR PHASE-ONLY FEEDBACK AND CORRESPONDING PIGGYBACK FEEDBACK FORMAT WITHIN SINGLE USER, MULTIPLE USER, MULTIPLE ACCESS, AND/OR MIMO WIRELESS COMMUNICATIONS“ (Vertreteraktenzeichen BP31536), eingereicht am 5.11.2012; und
2. 2. Vorläufige US-Anmeldung Nr. 61/805,855 mit dem Titel „CHANNEL ESTIMATION FOR PHASE-ONLY FEEDBACK AND METHODS FOR USE THEREWITH“ (Vertreteraktenzeichen BP31536.1), eingereicht am 27.3.2013.

This ordinary U.S. patent application claims priority under 35 USC § 119 (e) from the following tentative U.S. patent applications, which are incorporated herein by reference in their entirety for all purposes and are made a part of this ordinary U.S. patent application:

1. 1. Preliminary U.S. Application No. 61 / 722,279 entitled "CHANNEL ESTIMATION FOR PHASE-ONLY FEEDBACK AND CORRESPONDING PIGGYBACK FEEDBACK FORMAT WITHIN SINGLE USER, MULTIPLE USER, MULTIPLE ACCESS, AND / OR MIMO WIRELESS COMMUNICATIONS" (representative number BP31536), filed on November 5, 2012; and
2. 2. Preliminary U.S. Application No. 61 / 805,855 entitled "CHANNEL ESTIMATION FOR PHASE-ONLY FEEDBACK AND METHODS FOR USE THEREWITH" (representative file number BP31536.1), filed on March 27, 2013.

1. 1. IEEE Std 802.11™ - 2012, „IEEE Standard for Information technology-Telecommunications and information exchange between systems-Local and metropolitan area networks-Specific requirements; Part 11: Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) Specifications,“ IEEE Computer Society, gesponsert durch LAN/MAN Standards Committee, IEEE Std 802.11™-2012, (Überarbeitung von IEEE Std 802.11-2007), 2793 Seiten insgesamt (umfassend Seiten i-xcvi, 1-2695).
2. 2. IEEE Std 802.11n™ - 2009, „IEEE Standard for Information technology-Telecommunications and information exchange between systems-Local and metropolitan area networks-Specific requirements; Part 11: Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) Specifications; Amendment 5: Enhancements for Higher Throughput,“ IEEE Computer Society, IEEE Std 802.11n™-2009, (Änderung von IEEE Std 802.11™ - 2007, wie geändert durch IEEE Std 802.11k™ - 2008, IEEE Std 802.11r™ - 2008, IEEE Std 802.11y™ - 2008 und IEEE Std 802.11r™ - 2009), 536 Seiten insgesamt (umfassend Seiten i-xxxii, 1-502).
3. 3. IEEE P802.11ac™/D3.1, August 2012, „Draft STANDARD for Information Technology - Telecommunications and information exchange between systems - Local and metropolitan area networks - Specific requirements, Part 11: Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) specifications, Amendment 4: Enhancements for Very High Throughput for Operation in Bands below 6 GHz,“ erstellt durch 802.11 Working Group von 802 Committee, 391 Seiten insgesamt (umfassend Seiten i-xxv, 1-366).
4. 4. IEEE P802.11ad™/D9.0, Juli 2012, (Änderungsentwurf basierend auf IEEE 802.11-2012) (Änderung von IEEE 802.11-2012, wie geändert durch IEEE 802.11ae-2012 und IEEE 802.11aa-2012), „IEEE P802.11ad™/D9.0 Draft Standard for Information Technology - Telecommunications and Information Exchange Between Systems - Local and Metropolitan Area Networks - Specific Requirements - Part 11: Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) Specifications - Amendment 3: Enhancements for Very High Throughput in the 60 GHz Band,“ Sponsor: IEEE 802.11 Committee von IEEE Computer Society, IEEE-SA Standards Board, 679 Seiten insgesamt.
5. 5. IEEE Std 802.11ae™ - 2012, „IEEE Standard for Information technology-Telecommunications and information exchange between systems-Local and metropolitan area networks-Specific requirements; Part 11: Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) Specifications,“ „Amendment 1: Prioritization of Management Frames,“ IEEE Computer Society, gesponsert durch LAN/MAN Standards Committee, IEEE Std 802.11ae™-2012, (Änderung von IEEE Std 802.11™-2012), 52 Seiten insgesamt (umfassend Seiten i-xii, 1-38).
6. 6. IEEE P802.11af™/D1.06, März 2012, (Änderung von IEEE Std 802.11REVmb™/D12.0, wie geändert durch IEEE Std 802.11ae™/D8.0, IEEE Std 802.11aa™/D9.0, IEEE Std 802.11ad™/D5.0, und IEEE Std 802.11ac™/D2.0), „Draft Standard for Information Technology-Telecommunications and information exchange between systems-Local and metropolitan area networks-Specific requirements - Part 11: Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) Specifications - Amendment 5: TV White Spaces Operation,“ erstellt durch 802.11 Working Group von IEEE 802 Committee, 140 Seiten insgesamt (umfassend Seiten i-xxii, 1-118).

The following IEEE standards / draft standards are hereby incorporated by reference in their entirety for all purposes, and are made part of this ordinary U.S. patent application:

1. 1. IEEE Std 802.11 ™ - 2012, "IEEE Standard for Information technology-Telecommunications and information exchange between systems-Local and metropolitan area networks-Specific requirements; Part 11: Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) Specifications, “IEEE Computer Society, sponsored by LAN / MAN Standards Committee, IEEE Std 802.11 ™ -2012, (revision of IEEE Std 802.11-2007), 2793 Total pages (including pages i-xcvi, 1-2695).
2. 2. IEEE Std 802.11n ™ - 2009, "IEEE Standard for Information technology-Telecommunications and information exchange between systems-Local and metropolitan area networks-Specific requirements; Part 11: Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) Specifications; Amendment 5: Enhancements for Higher Throughput, “IEEE Computer Society, IEEE Std 802.11n ™ -2009, (change from IEEE Std 802.11 ™ - 2007 as amended by IEEE Std 802.11k ™ - 2008, IEEE Std 802.11r ™ - 2008, IEEE Std 802.11y ™ - 2008 and IEEE Std 802.11r ™ - 2009), 536 pages in total (including pages i-xxxii, 1-502).
3. 3. IEEE P802.11ac ™ / D3.1, August 2012, "Draft STANDARD for Information Technology - Telecommunications and information exchange between systems - Local and metropolitan area networks - Specific requirements, Part 11: Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) specifications, Amendment 4: Enhancements for Very High Throughput for Operation in Bands below 6 GHz, “created by 802.11 Working Group of 802 Committee, 391 pages in total (including pages i-xxv, 1-366).
4. 4. IEEE P802.11ad ™ / D9.0, July 2012, (Draft based on IEEE 802.11-2012) (Change from IEEE 802.11-2012 as modified by IEEE 802.11ae-2012 and IEEE 802.11aa-2012), "IEEE P802.11ad ™ / D9.0 Draft Standard for Information Technology - Telecommunications and Information Exchange Between Systems - Local and Metropolitan Area Networks - Specific Requirements - Part 11: Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) Specifications - Amendment 3: Enhancements for Very High Throughput in the 60 GHz Band, “Sponsor: IEEE 802.11 Committee from IEEE Computer Society, IEEE-SA Standards Board, 679 pages in total.
5. 5. IEEE Std 802.11ae ™ - 2012, "IEEE Standard for Information technology-Telecommunications and information exchange between systems-Local and metropolitan area networks-Specific requirements; Part 11: Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) Specifications, "" Amendment 1: Prioritization of Management Frames, "IEEE Computer Society, sponsored by LAN / MAN Standards Committee, IEEE Std 802.11ae ™ -2012, (Change from IEEE Std 802.11 ™ -2012), 52 pages in total (including pages i-xii, 1-38).
6. 6. IEEE P802.11af ™ / D1.06, March 2012, (change from IEEE Std 802.11REVmb ™ / D12.0 as changed by IEEE Std 802.11ae ™ / D8.0, IEEE Std 802.11aa ™ / D9.0 , IEEE Std 802.11ad ™ / D5.0, and IEEE Std 802.11ac ™ / D2.0), "Draft Standard for Information Technology-Telecommunications and information exchange between systems-Local and metropolitan area networks-Specific requirements - Part 11: Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) Specifications - Amendment 5: TV White Spaces Operation, “prepared by the 802.11 Working Group of the IEEE 802 Committee, 140 pages in total (including pages i-xxii, 1-118).

BACKGROUND OF THE INVENTION

TECHNICAL FIELD OF THE INVENTION

The invention relates generally to communication systems; and in particular, it relates to channel estimation in single-user, multi-user, multiple access and / or MIMO wireless communications.

DESCRIPTION OF THE RELATED ART

Communication systems are known to support wireless and wired communications between wireless and / or wired communication devices. Such communication systems range from national and / or international mobile or cellular telephone systems to the Internet up to in-house point-to-point wireless networks. Each type of communication system is constructed according to one or more communication standards and therefore works according to this or these. For example, wireless communication systems may operate in accordance with one or more standards that include, but are not limited to, IEEE 802.11x, Bluetooth, Advanced Mobile Phone Services (AMPS), Digital-AMPS, Global System for Mobile Communications (GSM), Code Division Mulitple Access (CDMA), Local Multi-Point Distribution Systems (LMDS), Multi-Channel-Multi-Point Distribution Systems (MMDS) and / or modifications of these.

Depending on the type of wireless communication system, a wireless communication device, such as a mobile or cellular telephone, a walkie-talkie, an organizer or mini-computer (PDA: “Personal Digital Assistant”), a workstation or personal computer (PC), a laptop computer , a home entertainment system, etc. directly or indirectly with other wireless communication devices. For direct communications (also known as point-to-point communications), the wireless communication devices involved tune their receivers and transmitters to the same channel or channels (e.g., one of the plurality of radio frequency (RF) carriers of the wireless communication system) and communicate through this channel or channels. For indirect wireless communications, each wireless communication device communicates directly via an assigned channel with an associated base station (e.g. for cellular services) and / or an associated access point (e.g. for an in-house or indoor wireless network). In order to complete a communication link between the wireless communication devices, the associated base stations and / or the associated access points communicate directly with one another via a system control unit, via the public telephone network, via the Internet and / or via another long-distance network or further traffic network.

For each wireless communication device, in order to participate in wireless communications, it includes a built-in radio transceiver (ie receiver and transmitter) or with an associated radio transceiver (e.g. a station for in-house and / or in-house wireless communication networks, an RF modem, etc.) is coupled. As is known, the receiver is coupled to the antenna and includes a low noise amplifier, one or more intermediate frequency stages, a filter stage and a data recovery stage. The low-noise amplifier receives incoming RF signals via the antenna and amplifies it. The one or more intermediate frequency stages mix the amplified RF signals with one or more local oscillations to convert the amplified RF signals into baseband signals or intermediate frequency (IF) signals. The filter stage filters the baseband signals or the IF signals so that unwanted signals outside the band are attenuated to produce filtered signals. The data recovery stage restores raw data from the filtered signals in accordance with the special wireless communication standard.

As is also known, the transmitter comprises a data modulation stage, one or more intermediate frequency stages and a power amplifier. The data modulation stage converts raw data into baseband signals in accordance with the special wireless communication standard. The one or more intermediate frequency stages mix the baseband signals with one or more local oscillations to generate RF signals. The power amplifier amplifies the RF signals before being sent via an antenna.

Typically, the transmitter will include an antenna for transmitting the RF signals received by a single antenna or multiple antennas of a receiver. If the receiver comprises two or more antennas, the receiver will select one of them to receive the incoming RF signals. In this case, the wireless communication between the transmitter and the receiver is a single-input-single-output (SISO: "Single-Input-Single-Output) communication, even if the receiver comprises several antennas that are used as diversity antennas (i.e. by one of these is selected to receive the incoming RF signals). For SISO wireless communications, a transceiver includes a transmitter and a receiver. Most are currently using wireless local area networks (WLAN), namely IEEE 802.11, 802.11a, 802.11b or 802.11g SISO wireless communications.

Other types of wireless communications include single input multiple output (SIMO: "single input multiple output), multiple input single output (MISO:" multiple input signal output ") and multiple input multiple output (MIMO:" multiple input Multiple-output "). With SIMO wireless communication, a single transmitter processes data into radio frequency signals that are sent to a receiver. The receiver comprises two or more antennas and two or more reception paths. Each of the antennas receives the RF signals and delivers them to a corresponding reception path (e.g. LNA, downconversion module, filter and ADCs). Each of the receive paths processes the received RF signals to produce digital signals that are combined and then processed to recover the transmitted data.

For multiple input single output (MISO) wireless communication, the transmitter includes two or more transmit paths (e.g. digital-to-analog converter, filter, upconversion module and power amplifier), each of which converts a corresponding proportion of baseband signals into RF signals, which are transmitted via corresponding antennas be sent to a recipient. The receiver includes a single receive path that receives the multiple RF signals from the transmitter. In this case, the receiver uses beamforming to combine the multiple RF signals into one signal for processing.

For multiple input multiple output (MIMO) wireless communication, the transmitter and receiver each span multiple paths. In such communication, the transmitter processes data in parallel using a space and time coding function to generate two or more data streams. The transmitter comprises several transmission paths in order to convert each data stream into several RF signals. The receiver receives the multiple RF signals over multiple receive paths that recover the data streams using a space and time decoding function. The recovered data streams are combined and then processed to restore the original data.

With the different types of wireless communications (e.g. SISO, MISO, SIMO and MIMO) it would be desirable to use one or more types of wireless communications to increase data throughput in a WLAN. For example, MIMO communications can achieve high data rates compared to SISO communications. However, most WLANs include legacy wireless communication devices (i.e., devices that conform to an older version of a wireless communication standard). In this respect, a transmitter suitable for MIMO wireless communications should also be backwards compatible with old or conventional devices in order to function in the majority of existing WLANs. The disadvantages of conventional approaches will become apparent to those skilled in the art upon presentation of the following disclosure.

US 2007/0 133 458 A1 describes a method and system for providing control information to support high speed downlink and high speed uplink packet access. A knot B has a wireless transmitter / receiver unit ( WTRU ) at least one downlink control channel and at least one uplink control channel. The downlink control channel and the uplink control channel are provided to transmit control information for both the downlink and the uplink. The WTRU receives downlink data and transmits uplink data, and the node B receives uplink data and transmits downlink data based on the control information transmitted via the downlink control channel and the uplink control channel.

US 2008/0 069 031 A1 describes an additional MAC functionality that supports the PHY features of a frame for a wireless communication system. The additional MAC functionality enables the feedback from wireless end devices to base stations, the feedback being able to be provided on an assigned feedback channel.

DE 10 2008 023 105 A1 describes a device for achieving a robust channel estimation in a communication system, which comprises a training sequence generator for generating a training sequence. Formatting puts the training sequence in a frame. A transmitter module is used to send the frame. The training sequence generator further comprises a symbol generator for generating a plurality of training symbols that meet a predetermined boundary condition such that the training symbols are insensitive to a synchronization error, and a training sequence formation unit that forms the training sequence from the training symbols generated by the training symbol generator.

list of figures

• 1 FIG. 12 is a diagram illustrating an embodiment of a wireless communication system.
• 2 FIG. 12 is a diagram illustrating an embodiment of a wireless communication device.
• 3 Fig. 14 is a diagram showing an embodiment of an access point ( AP ) and multiple wireless local area network (WLAN) devices that operate in accordance with one or more diverse aspects and / or embodiments of the invention.
• 4 FIG. 12 is a diagram illustrating one embodiment of a wireless communication device and cluster as they can be used to support communications with at least one other wireless communication device.
• 5 illustrates an embodiment of OFDM (Orthogonal Frequency Division Multiplex).
• 6 illustrates an embodiment of a number of wireless communication devices implemented in different locations in an environment that includes a building or structure.
• 7 illustrates one embodiment of a number of wireless communication devices implemented at different locations in a vehicle environment.
• 8th illustrates one embodiment of a number of wireless communication devices implemented in different locations across a widely used industrial environment.
• 9 illustrates an embodiment of a probing process with a null data packet ( NDP ).
• 10 illustrates an embodiment of a performance diagram with a space channel model ( SCM ) at 900 MHz (31.25 kHz).
• 11 illustrates an embodiment of a further performance diagram (example 1).
• 12 illustrates an embodiment of a further performance diagram (example 2).
• 13 An embodiment of a performance diagram illustrates the effect on phase-aligned space-time block coding ( STBC ) shows.
• 14 illustrates one embodiment of providing feedback (FB) information using ACK (e.g., a combined ACK and FB exchange).
• 15 illustrates an embodiment of a FACK frame format.

DETAILED DESCRIPTION OF THE INVENTION

1 FIG. 12 is an illustration showing an embodiment of a wireless communication system 10 illustrates a variety of base stations and / or access points 12-16 , a variety of wireless communication devices 18-23 and a network hardware component 34 includes. The wireless communication devices 18-23 can laptop host computers 18 and 26 , Organizer or mini computer hosts 20 and 30 , Personal computer hosts 24 and 32 and / or mobile phone hosts 20 and 28 his. The details of an embodiment of such wireless communication devices are with reference to FIG 2 described in more detail.

The base stations ( BSs ) or access points ( APs ) 12-16 are over local area network connections 36 . 38 and 40 operational with the network hardware 34 coupled. The network hardware 34 which can be a router, a switch, a bridge, a modem, a system control unit, etc., provides a wide area network connection 42 for the communication system 10 ready. Any of the base stations or access points 12-16 has an associated antenna or antenna group to communicate with the wireless communication devices in its area. Typically, the wireless communication devices register with a particular base station or access point 12-14 to provide services from the communication system 10 to recieve. For direct connections (ie, point-to-point communications), wireless communication devices communicate directly over an assigned channel.

Typically, base stations for mobile or cellular telephone systems (e.g. Advanced Mobile Phone Services (AMPS), Digital-AMPS, Global System for Mobile Communications (GSM), Code Division Multiple Access (CDMA), Local Multi-Point Distribution Systems (LMDS), Multi-Channel-Multi-Point Distribution Systems (MMDS), Enhanced Data Rates for GSM Evolution (EDGE), General Packet Radio Service (GPRS), High-Speed Downlink Packet Access (HSDPA), High-Speed Uplink Packet Access (HSUPA) and / or modifications of these) and systems of a similar type, while access points for in-house or in-house wireless networks (e.g. IEEE 802.11, Bluetooth, ZigBee, any other type of radio frequency-based network protocol and / or modifications of these) are used. Regardless of the particular type of communication system, each wireless communication device includes a built-in radio unit and / or is coupled to a radio unit. Such wireless communication devices can operate in accordance with the various aspects of the invention as set forth herein to improve performance, reduce cost, reduce size, and / or expand broadband applications.

2 FIG. 12 is a diagram illustrating an embodiment of a wireless communication device that the host device 18-32 and an associated radio unit 60 includes. The radio unit is for mobile or cellular telephone hosts 60 a built-in component. The radio unit can be used for organizer or mini computer hosts, laptop hosts and / or personal computer hosts 60 built-in or an externally coupled component. For access point or base stations, the components are typically housed in a single structure or body.

As illustrated, the host device comprises 18-32 a processing module 50 , a memory 52 , a radio interface 54 , an input interface 58 and an output interface 56 , The processing module 50 and the memory 52 execute the appropriate instructions typically given by the host device. For example, the processing module performs 50 for a mobile phone host device, the corresponding communication functions according to a special mobile phone standard.

The radio interface 54 allows data from the radio unit 60 received and sent to them. At from the radio unit 60 The radio interface supplies received data (eg incoming data) 54 the data to the processing module 50 for further processing and / or routing to the output interface 56 , The output interface 56 provides connectivity to an output device such as a display, monitor, speakers, etc. so that the received data can be played back. The radio interface 54 also provides data from the processing module 50 to the radio unit 60 , The processing module 50 can send the outgoing data from an input device such as a keyboard, a keypad, a microphone, etc. via the input interface 58 received or generate the data yourself. For data using the input interface 58 can be received, the processing module 50 perform a corresponding host function on the data and / or this via the radio interface 54 to the radio unit 60 to steer.

The radio module 60 includes a host interface 62 , a baseband processing module 64 , a memory 66 , a variety of radio frequency (RF) transmitters 68 to 72 , a transmit / receive (T / R) module 74 , a variety of antennas 82 to 86 , a variety of RF receivers 76-80 and a local oscillation module 100 , The baseband processing module 64 leads, in combination with operational instructions, in memory 66 are stored, digital receiver functions and the digital transmitter functions. The digital receiver functions include, but are not limited to, digital intermediate frequency baseband conversion, demodulation, constellation demapping, decoding, deinterleaving, fast Fourier transform, cyclic prefix removal, space and time decoding and / or descrambling. The digital transmitter functions, as described in more detail with reference to later figures, include, but are limited to, scrambling, coding, interleaving, constellation mapping, modulation, inverse fast Fourier transformation, addition of cyclic prefix, space and time coding and / or digital baseband IF conversion. The baseband processing module 64 may be implemented using one or more processing devices. Such a processing device can be a microprocessor, a microcontroller, a digital signal processor, a microcomputer, a central processing unit, a field programmable gate array, a programmable logic device, a state machine, a logic circuit, an analog circuit, a digital circuit and / or any device that manipulates or processes (analog and / or digital) signals based on operational instructions. The memory 66 may be a single storage device or a plurality of storage devices. Such a memory device may be read-only memory, random access memory, volatile memory, non-volatile memory, static memory, dynamic memory, flash memory and / or any device that stores digital information. Note that the memory that stores the corresponding operational instructions is embedded in the circuitry that includes the state machine, analog circuitry, digital circuitry, and / or logic circuitry when the processing module 64 implements one or more of its functions via a state machine, an analog circuit, a digital circuit and / or a logic circuit.

The radio unit receives during operation 60 outgoing data 88 from the host device through the host interface 62 , The baseband processing module 64 receives the outgoing data 88 and generated based on a mode selection signal 102 one or more outgoing symbol streams 90 , The Mode select signal 102 will designate a particular mode as illustrated in the mode selection tables that appear at the end of the detailed description. For example, the mode selection signal 102 refer to Table 1 for a frequency band of 2.4 GHz or 5 GHz, a channel bandwidth of 20 or 22 MHz (eg channels of a width of 20 or 22 MHz) and a maximum bit rate of 54 megabits per second. In other embodiments, the channel bandwidth can extend up to 1.28 GHz or wider, with supported maximum bit rates extending up to 1 gigabit per second or greater. In this general category, the mode selection signal will continue to designate a certain rate ranging from 1 megabit-per-second to 54 megabit-per-second. In addition, the mode selection signal will denote a particular type of modulation that includes, but is not limited to, Barker code modulation, BPSK, QPSK, CCK, 16-QAM, and / or 64-QAM. A code rate can be selected as well as a number of coded bits per sub or subcarrier (NBPSC), coded bits per OFDM symbol (NCBPS), data bits per OFDM symbol (NDBPS).

The mode selection signal can also denote a specific channeling or channel design for the corresponding mode, which comprises a channel number or number and a corresponding center frequency. The mode selection signal may further denote a power spectral density mask value. The mode selection signal can denote, for example, a 5 GHz frequency band, a 20 MHz channel bandwidth and a maximum bit rate of 54 megabits per second. As a further alternative, the mode selection signal 102 denote a 2.4 GHz frequency band, 20 MHz channels and a maximum bit rate of 192 megabits per second. The mode selection signal would also indicate the number of antennas to be used. It is of course to be noted that other types of channels having different bandwidths can be used in other embodiments without departing from the scope and idea of the invention. For example, various other channels, such as those with a bandwidth of 80 MHz, 120 MHz and / or 160 MHz, can be used optionally, such as in accordance with IEEE Task Group ac (TGac VHTL6).

The baseband processing module 64 generated based on the mode selection signal 102 the one or more outgoing symbol streams 90 from the output data 88 , For example, if the mode selection signal 102 indicates that a single transmit antenna is to be used for the particular mode that has been selected becomes the baseband processing module 64 a single outgoing symbol stream 90 produce. Optional if the mode selection signal 2 . 3 or 4 Called antennas, the baseband processing module 64 2 . 3 or 4 outgoing symbol streams 90 corresponding to the number of antennas from the output data 88 produce.

Depending on the number of outgoing streams 90 by the baseband module 64 will be generated, a corresponding number of RF transmitters 68-72 activated the outgoing symbol streams 90 in outgoing RF signals 92 to walk. The send / receive module 74 receives the outgoing RF signals 92 and delivers each outgoing RF signal to a corresponding antenna 82-86 ,

If the radio module 60 is in the receive mode, the transmit / receive module receives 74 one or more incoming RF signals via the antennas 82-86 , The T / R module 74 delivers the incoming RF signals 94 to one or more RF receivers 76-80 , The RF receiver 76-80 converts the incoming RF signals 94 into a corresponding number of incoming symbol streams 96 , The number of incoming symbol streams 96 will correspond to the particular mode in which the data was received (remembering that the mode can be any of the modes illustrated in Tables 1-12). The baseband processing module 64 receives the incoming symbol streams 90 and converts this into incoming data 98 that through the host interface 62 to the host device 18-32 to be delivered.

In one embodiment of the radio unit 60 this comprises a transmitter and a receiver. The transmitter can include a MAC module, a PLCP module and a PMD module. The MAC module (MAC: "Medium Access Control"), which with / in the processing module 64 is operationally coupled to a MAC service data unit ( MSDU ) according to a WLAN protocol into a MAC protocol data unit ( MPDU ) to walk. The PLCP module ( PLCP : "Physical Layer Convergence Procedure"), which with / in the processing module 64 can be operationally coupled to the MPDU according to the WLAN protocol into a PLCP protocol data unit ( PPDU ) to walk. The PMD module ( PMD : "Physical Medium Dependent") is operationally coupled to convert the PPDU into a variety of radio frequency (RF) signals in accordance with one of a variety of modes of operation of the WLAN protocol, the variety of modes of operation having multiple input and multiple output combinations includes.

An embodiment of the PMD module ( PMD : "Physical Medium Dependent") includes an error protection or error protection module Demultiplex module and a variety of direct or direction conversion modules. The error protection or error protection module that with / in the processing module 64 can be implemented is operationally linked to a PPDU (PLCP protocol data unit ( PLCP : "Physical Layer Convergence Procedure")) to be restructured to reduce transmission errors, which creates error-protected data. The demultiplexing module is operationally coupled in order to divide the error-protected data into a large number of error-protected data streams. The plurality of direct or directional conversion modules are operationally coupled to convert the plurality of error-protected data streams into a variety of radio frequency (RF) signals.

As one skilled in the art will recognize, the wireless communication device can be configured according to 2 be implemented using one or more integrated circuits. For example, the host device can be implemented on an integrated circuit, the baseband processing module 64 and the memory 66 be implemented on a second integrated circuit, and the remaining components of the radio unit 60 , except the antennas 82-86 , to be implemented on a third integrated circuit. As an alternative example, the radio unit 60 be implemented on a single integrated circuit. As yet another example, the processing module 50 the host device and the baseband processing module 64 represent a common processing device implemented on a single integrated circuit. Furthermore, the memory 52 and the memory 66 on a single integrated circuit and / or on the same integrated circuit as the common processing modules of the processing module 50 and baseband processing module 64 be / will be implemented.

3 Fig. 14 is a diagram showing an embodiment of an access point ( AP ) and multiple wireless local area network (WLAN) devices that operate in accordance with one or more diverse aspects and / or embodiments of the invention. The AP 300 may be compatible with any number of communication protocols and / or standards, e.g. IEEE 802.11 (a), IEEE 802.11 (b), IEEE 802.11 (g), IEEE 802.11 (n), as well as in accordance with various aspects of the invention , According to certain aspects of the present invention, the AP also backward compatibility with previous versions of the IEEE 802.11x standards. According to further aspects of the present invention, the AP 300 Communications with the WLAN devices 302 . 304 and 306 with channel bandwidths, MIMO dimensions and data throughput rates that are not supported by the previous IEEE 802.11x operating standards. For example, the access point 300 and the WiFi devices 302 . 304 and 306 Support channel bandwidths from those of devices of previous versions and from 40 MHz to 1.28 GHz and above. The access point 300 and the WiFi devices 302 . 304 and 306 support MIMO dimensions up to 4x4 and above. With these properties, the access point 300 and the WiFi devices 302 . 304 and 306 Support data throughput rates of 1 GHz and above.

The AP 300 supports simultaneous communications with more than one of the WLAN devices 302 . 304 and 306 , Simultaneous communications can be operated or maintained using OFDM tone assignments (for example, a certain number of OFDM tones in a particular cluster), MIMO dimension multiplexing or other techniques. With some simultaneous communications, the AP 300 Assign one or more of its multiple antennas, for example, to communicate with each WLAN device 302 . 304 and 306 to support.

Furthermore, the AP 300 and the WiFi devices 302 . 304 and 306 backwards compatible with the IEEE 802.11 (a), (b), (g) and (n) operating standards. By supporting such backward compatibility, these devices support signal formats and structures that are vainable with these earlier operating standards.

In general, communications as described herein may be for reception by a single receiver or multiple individual receivers (e.g., via multi-user, multi-input, multi-output (MU-MIMO) and / or OFDMA transmissions that differ from individual Differentiate transmissions with a multiple recipient address). For example, a single OFDMA transmission uses different tones or sets of tones (e.g. clusters or channels) to send different sets of information, with each set of information being transmitted to one or more recipients in the time domain simultaneously. An OFDMA transmission sent to a user is in turn equivalent to an OFDM transmission (eg OFDM can be viewed as a subset of OFDMA). A single MU-MIMO transmission can include spatially separated signals over a common set of tones, each containing different information and each being transmitted to one or more different receivers. Some individual transmissions can be a combination of OFDMA and MU-MIMO. The term multi-user (MU) as he Described herein may be considered to refer to multiple users sharing or sharing at least one cluster (eg, at least one channel within at least one band) at the same time.

The MIMO transceivers shown can include SISO, SIMO and MISO transceivers. The clusters used for such communications (for example OFDMA communications) can be continuous (for example adjacent to one another) or discontinuous (for example separated by a guard interval or a band gap). Transfers on different OFDMA clusters can be simultaneous or non-simultaneous. Such wireless communication devices, as described herein, may be capable of supporting communications across a single cluster or any combination thereof. Old or conventional users and users of a newer version (eg TGac MU-MIMO, OFDMA, MU-MIMO / OFDMA, etc.) can share or share a bandwidth at a certain time, or they can for different embodiments at different times be scheduled. Such a MU-MIMO / OFDMA transmitter (e.g. AP or STA) can transmit packets to more than one receiving wireless communication device (e.g. STA) on the same cluster (e.g. at least one channel within at least one band) in a single merged packet (such as time-division multiplexed). In such a case, channel training may be required for all communication links to the respective receiving wireless communication devices (eg STAs).

4 FIG. 14 is a diagram illustrating an embodiment of a wireless communication device and cluster as used to support communications with at least one other wireless communication device. Generally speaking, a cluster can be viewed as a representation of the assignment of tones, such as for an OFDM symbol, within or between one or more channels (e.g., divided parts of the spectrum) that are in one or more bands (e.g., parts of the spectrum) , which are separated by relatively large amounts). As an example, different 20 MHz channels may be in or centered around a 5 GHz band. The channels within each such band can be continuous (eg adjacent to each other) or discontinuous (eg separated by a guard interval or a band gap). Often one or more channels can be in a certain band and different bands do not necessarily have to have the same number of channels. Again, a cluster can generally be understood as any combination of one or more channels under / between one or more bands.

The wireless communication device according to this illustration may be of any of the various types and / or equivalents described herein (e.g., including an AP, WLAN device, or other wireless communication device including, but not limited to, any of those described in 1 , etc. are shown). The wireless communication device includes a plurality of antennas, one or more signals of which can be sent to one or more receiving wireless communication devices and / or received by one or more other wireless communication devices.

Such clusters can be used to transmit signals over different antennas selected from one or more. For example, different clusters are shown to be used to transmit signals each using one or more antennas.

It should also be noted that a general nomenclature may be used with respect to certain embodiments, where a sending wireless communication device (e.g., such as an access point ( AP ) or a wireless station ( STA ) that operates as an "AP" with respect to other STAs) with respect to a number of other received wireless communication devices (e.g., such as STAs) initiates communications and / or operates as a network controller of a wireless communication device, and the receiving wireless ones Communication devices (e.g., such as STAs) to support and cooperate with the transmitting wireless communication device to support such communications. Of course, while this general nomenclature can be used by sending wireless communication devices and receiving wireless communication devices to differentiate between the operations performed by different wireless communication devices in a communication system, all such wireless communication devices can of course be used in such a communication system Support bidirectional communications to and from other wireless communication devices in the communication system. In other words, the different types of sending wireless communication devices and receiving wireless communication devices can each be bidirectional communications to and from other wireless devices Support communication devices in the communication system. Generally speaking, such capability, functionality, operations, etc., as described herein, may be applied to any wireless communication device.

Various aspects and principles, as well as their equivalents, in accordance with the invention as set forth herein may be adapted for use in various standards, protocols, and / or recommended methods / applications (including those currently under development) such as those according to IEEE 802.11x (where x is, for example, a, b, g, n, ac, ad, ae, af, ah, etc.).

5 illustrates an embodiment 500 of OFDM (Orthogonal Frequency Division Multiplexing). An OFDM modulation can be viewed as a division of an available spectrum into a multiplicity of narrow-band sub-carriers or sub-carriers (for example carriers with a lower data rate). Typically, the frequency responses from these subcarriers are overlapping and orthogonal. Each subcarrier can be modulated using any of a variety of modulation coding techniques.

ODFM modulation works by performing a simultaneous transmission of a larger number of narrowband carriers (or multiple tones). Often, a guard interval (GI: "Guard Interval") or a protective space between the different ODFM symbols is used to minimize the effects of ISI (intersymbol interference), which can be caused by the effects of multiple paths within the communication system (which is of particular importance for wireless communication systems). In addition, a cyclic prefix (CP: "Cyclic Prefix") can be used within the protection interval to ensure a switchover time (when jumping to a new band) and to help maintain the orthogonality of the OFDM symbols. Generally speaking, the design of the OFDM system is based on the expected delay spread or expansion within the communication system (e.g. the expected delay spread or expansion of the communication channel).

In certain cases, various wireless communication devices may be implemented to support communications associated with monitoring and / or sensing any of a variety of different conditions, parameters, etc., and such information to another deliver wireless communication device. For example, in some cases, a wireless communication device can be implemented as an intelligent metering station (SMSTA: "Smart Meter Station") that has certain properties similar to those of a wireless station ( STA ), such as in the context of a wireless local area network (WLAN), but is operable to perform such communications related to one or more measurements according to monitoring and / or sensing. In certain applications, such devices can only work very rarely. For example, compared to the time periods in which such a device is in a power saving mode (e.g. a sleep mode, an operating mode with reduced functionality, a low energy operating mode, etc.), the operating time periods can be comparatively small (e.g. only a few percent of the time periods in which) the device is in such an energy-saving mode).

For example, such a device can only wake up from such an energy-saving mode in order to carry out certain operations or operations. For example, such a device can wake up from such an energy-saving mode in order to carry out a sensing or / or measurement and / or measurement of one or more parameters, conditions or conditions, restrictions or constraints, etc. During such an operating period (for example in which the device is not in an energy-saving mode), the device can also transmit such information to another wireless communication device (for example an access point ( AP ), another SMSTA, a wireless station ( STA ) or such an SMSTA or STA that as a AP works, etc.). It should be noted that such a device can enter an operating mode for performing a sensing or / and monitoring with a frequency or frequency that is different from (eg greater) the frequency or frequency with which the device enters an operating mode for performing transfers. For example, such a device may wake up a certain number of times to perform respective sequential sensing or / and monitoring operations, and such data as acquired during these operations may be stored (e.g., in a memory component in the device) and during a subsequent mode of operation intended for the transmission of the data, a plurality of pieces of data corresponding to the respective plurality of sensing or scanning and / or monitoring processes can be carried out during this mode of operation intended for the transmission of the data be transmitted.

It should also be noted that, in certain embodiments, such a device may include monitoring and / or sensing or scanning capability as well as wireless communication capabilities. In some embodiments, such a device may be connected and / or coupled to a monitoring unit and / or a sensor and may be used to effect wireless communications related to the monitoring and / or sensing or sensing operations of the monitoring unit and / or the sensor.

The application contexts of such devices can be diverse, and some exemplary but not exhaustive list of exemplary embodiments are given in the description below for the reader's convenience. It should also be noted that in some applications, some of the devices may be battery operated, where energy saving and efficiency can be of great importance. In addition, there are a number of applications in which such devices can also be used according to intelligent measurement applications; for example, certain wireless communication devices may be implemented to support cellular offloading and / or other applications that are typically or conventionally unrelated to WLAN applications. Some applications are particularly targeted and directed toward use in accordance with and in accordance with the IEEE 802.11ah standard currently under development.

Different mechanisms by which access to the communication media can be achieved can be different and specially tailored for different contexts. For example, different communication access models can be used at different times. This means that a first communication media access approach can be used during a first time or during a first time period, and a second communication media access approach can be used during a second time or during a second time period. It should be noted that the particular communication media access approach that is used at a particular time can be adaptively determined based on one or more previous communication media access approaches that are used during one or more time periods.

Also, in an application in which a plurality of wireless communication devices are implemented, different time periods can be used for different groups of these wireless communication devices. For example, when considering an embodiment in which a plurality of STAs are operable in a particular communication device, these respective STAs can be divided into respective different groups, which can have access to the communication medium at different time periods. It should be noted that each given STA can be categorized into more than one group, inasmuch as different groups of STAs can have some overlap in their respective contents. By using different time periods for use by different groups of devices, an increase in media access control (MAC) efficiency can be achieved between / among all or more of the respective devices in the wireless communication system. By ensuring a suitable operation of the overall system, energy consumption can also be reduced as well. As mentioned above, this may be of paramount importance in certain applications, such as those in which one or more of the devices are battery powered and energy saving is of paramount importance. Using different time periods for use by different groups of STAs can also facilitate simplification according to MAC or PHY (PHY: "physical layer" or physical layer) processing. For example, certain embodiments may use preamble processing (e.g., in accordance with a distinction between communications of a normal range type and / or an extended range type) for simplification. In addition, the MAC protocol used for certain specific time periods can be simplified.

Note that the various aspects and their equivalents of the invention described herein can generally be applied to wireless communication devices that include any number of types of wireless communication devices (e.g., STAs, APs , SMSTAs and / or any combination of these, etc.), with certain desired embodiments being particularly tailored for use with one or more SMSTAs.

6 illustrates an embodiment 600 of a number of wireless communication devices implemented in different locations of an environment that includes a building. In this illustration, several wireless communication devices for forwarding information are included Implemented with respect to monitoring and / or sensing to a particular wireless communication device that can operate as a manager, coordinator, etc., such as that provided by an access point ( AP ) or a wireless station (STA) operating as a AP works, can be implemented. Generally speaking, such wireless communication devices can be implemented to perform any of a number of data forwarding, monitoring, and / or sensing or scanning operations. For example, in connection with a building, there may be a number of services provided for that building, including natural gas, power, television, internet, etc. Optionally, all Different monitoring units and / or sensors can be implemented in the environment in order to carry out monitoring and / or sensing or scanning with reference to parameters that are not specifically related to such services. As some examples, motion detection, temperature measurement (and / or other atmospheric and / or environmental measurements), etc. can be performed by different monitoring units and / or sensors implemented in different locations and for different purposes.

Different monitoring units and / or sensors can be implemented to wirelessly deliver information related to such monitoring and / or sensing or scanning functions to the wireless communication device representing the manager / coordinator. Such information can be provided continuously, sporadically, periodically or intermittently, etc., as may be desired in certain applications.

In addition, it should be noted that such communications between such a wireless communication device representing the manager / coordinator and the different monitoring units and / or sensors can be cooperative in accordance with such bidirectional messages, insofar as the wireless communication device representing the manager / coordinator is the respective monitoring units and / or May instruct sensors to perform certain associated functions at subsequent times.

7 illustrates an embodiment 700 of a number of wireless communication devices implemented in different locations in a vehicle environment. This illustration shows a number of different sensors implemented across a vehicle, which can perform any of a number of monitoring and / or sensing or scanning functions. For example, operational properties related to different mechanical components (e.g. temperature, operating condition, etc., of any of a number of components within the vehicle, such as the engine, compressors, pumps, batteries, etc.) can be monitored, and information related to this monitoring can be provided to a coordinator / manager wireless communication device.

8th illustrates an embodiment 800 of a number of wireless communication devices implemented in different locations across a common industrial environment. This illustration depicts a number of different sensors that can be implemented in different locations, which can be very far away from one another. This illustration relates to a number of sensors that can be implemented in different locations to which little or no wireless communication infrastructure can be connected. For example, different pumps can be implemented in very remote locations in the oil industry and service personnel must physically visit the respective different locations in order to explore or check the operation of various systems and components there. A manager / coordinator wireless communication device may be implemented in a vehicle or in a portable component, such as a laptop computer, that is located in the vehicle and the vehicle travels to any location where such sensing or scanning and / or monitoring devices. If the wireless communication device representing the manager / coordinator comes sufficiently close to support wireless communication with the different sensing and / or monitoring devices, information related to such monitoring and / or sensing or monitoring devices can be provided Scanning functions are provided to the wireless communication device representing the manager / coordinator.

While various and exemplary embodiments have been provided here for the reader's sake of illustration, it should be noted that such applications are non-exhaustive and that any of a variety of application contexts may be implemented such that one or more wireless communication devices are implemented across an area can be, so that these one or more wireless communication devices only temporarily send information to a manager / Can provide coordinating wireless communication device. Any such application or communication system can operate in accordance with various aspects and their equivalents to the invention.

Various aspects, embodiments, and / or their equivalents in accordance with the invention are directed to providing a novel design of a feedback frame for a single current. According to such a feedback, a phase-aligned space-time block coding (STBC: "Space Time Block Coding") can be made possible and a beam shaping for a noticeable gain or use can be made using pure phase information (such a feedback, for example, at least pure phase information includes) can be used. There is a consideration regarding feedback overhead or additional effort with regard to the current feedback format. For example, a null data packet (NDP) frame format requires a relatively large amount of additional network overhead to send a probe frame. According to such an operation, the feedback information reduction when viewing the NDP frames can become marginal in certain situations.

9 illustrates an embodiment 900 of a probing process with zero data packet ( NDP ). With reference to this illustration, operation is performed using 2 TX probing (2 MHz). According to such operation, NDP-A has 9 OFDM symbols for PHY preamble and 8 OFDM symbols for PHY payload. The NDP has 10 ODFM symbols. The probe feedback ( FB ) has 9 + 12 + 4 OFDM symbols (MCS0 with tone grouping of 4). Even if the angle information is reduced by a factor of half (eg only phase), the probing FB becomes 9 + 12 + 2 OFDM symbols. In some exemplary embodiments, a certain number of (eg 4) short interframe spaces (SIFSs: “Short Interframe Spaces”) can also be added.

The use of pure phase information or only phase information according to feedback with feedback of only a few bits per tone can provide a reasonably accurate channel estimate in some cases. For example, if desired, a quick estimation and go approach or a quick estimation and proceeding approach may be sufficient. Using such an approach would avoid any need to estimate the channel with the quality of about -30 dB MSE (mean square error). With only a few bits of quantization for one or two parameters, such an operation can already have a relatively or rather bad quantization error. However, in some applications, an MSE quality of -5 to -10 dB may be reasonable, acceptable, or good enough for that purpose.

A description of such a shortened channel estimate is given below. For an Nt × 1 configuration, a transmitter can send a single stream packet with a long training field (LTF: "Long Training Field"). An estimate of Nt × 1 channels can be made from an LTF without initiating NDP probing frames. Such feedback information (e.g. a few bytes) can be sent to the sending wireless communication device (e.g. access point ( AP ), wireless station ( STA ), as AP works, etc.) by piggyback (e.g. as in 15 ) are returned. Such a receiving wireless communication device (e.g., STA, etc.) can also group Ng tones for a channel estimation process.

A receiving wireless communication device (e.g., STA) groups Ng tones for a channel estimation process as follows: $$\left[\begin{array}{l}{\mathrm{<figure-callout\; id="1"\; label="y\; k"\; filenames="DE102013222328B4\_0008.png,DE102013222328B4\_0011.png"\; state="\{\{state\}\}">y\; </figure-callout>}}_k\hfill \\ ⋮\hfill \\ y_{kNG}\hfill \end{array}\right]=\left[\begin{array}{lll}{H}_{1\mathrm{<figure-callout\; id="1"\; label="k"\; filenames="DE102013222328B4\_0008.png,DE102013222328B4\_0011.png"\; state="\{\{state\}\}">k</figure-callout>}1}\hfill & \cdots \hfill & H_{\mathrm{<figure-callout\; id="1"\; label="N\; t\; k"\; filenames="DE102013222328B4\_0008.png,DE102013222328B4\_0011.png"\; state="\{\{state\}\}">N\; </figure-callout>}tk1}\hfill \\ ⋮\hfill & \ddots \hfill & ⋮\hfill \\ H_{1kNG}\hfill & \cdots \hfill & H_{NtkG}\hfill \end{array}\right]\times Q\times D\times T+N$$

Q is a unitary matrix, D is a diagonal CSD (CSD: "Cyclic Shift Delay" or cyclically shifted or offset delay) matrix and T is a large training vector (N is AWGN). Q, D and T can be different per tone k, ie Q is an Ng × (Nt Ng) matrix, D is an (Nt Ng) × (Nt Ng) block diagonal matrix and T is an (Nt Ng) × 1-column vector. Assuming h _ikj = h _ikm , where 1 <= j, m <= Ng and i = 1, ..., Nt, the channel h can be estimated from the received signal y as long as Ng> = Nt applies. In any case, the feedback information is grouped for each Ng tones.

Assuming h _ikj = h _ikm , the received signal can be expressed as follows: $$\begin{array}{l}\left[\begin{array}{ccc}{\tilde{y}}_{\mathrm{<figure-callout\; id="1"\; label="k"\; filenames="DE102013222328B4\_0008.png,DE102013222328B4\_0011.png"\; state="\{\{state\}\}">k</figure-callout>}1}& ...& {\tilde{y}}_{kNG}\end{array}\right]=\left[\begin{array}{ccc}{H}_{1k}& ...& H_{Ntk}\end{array}\right]\times \left[\begin{array}{ccc}{\mathrm{<figure-callout\; id="1"\; label="P\; k"\; filenames="DE102013222328B4\_0008.png,DE102013222328B4\_0011.png"\; state="\{\{state\}\}">P\; </figure-callout>}}_k& ...& P_{kNG}\end{array}\right]+N\\ {\tilde{y}}_k=y_k{\text{results from the assumption h}}_{\text{ikj}}={\text{H}}_{\text{ikm}}\end{array}$$

P _k = Q _k × D _k × T _k where Q _{k is} a unitary (Nt × Nt) matrix, P _{k is} a diagonal matrix with CSD (Nt × Nt), T _{k is} a training sequence (Nt × 1) and AWGN N (1 × Ng).

• W = P^H(PP^H + N₀I)^-1, wobei P = [P_k1 ... F_kNg] und N₀ ist die Leistung von AWGN-Rauschen gilt.

The channel estimator can be configured as follows:

• W = P ^H (PP ^H + N ₀ I) ^-1 , where P = [P _k1 ... F _kNg ] and N ₀ is the power of AWGN noise.

Then the estimated channel is as follows: $$\left[\begin{array}{ccc}{\widehat{H}}_{\mathrm{<figure-callout\; id="1"\; label="k"\; filenames="DE102013222328B4\_0008.png,DE102013222328B4\_0011.png"\; state="\{\{state\}\}">k</figure-callout>}1}& ...& {\widehat{H}}_{kNG}\end{array}\right]=\left[\begin{array}{ccc}{\mathrm{<figure-callout\; id="1"\; label="y\; k"\; filenames="DE102013222328B4\_0008.png,DE102013222328B4\_0011.png"\; state="\{\{state\}\}">y\; </figure-callout>}}_k& ...& y_{kNG}\end{array}\right]\times W$$

As such, there will be Nt variables for estimation using an inverse matrix of PP ^H. Thus, the condition number of the P matrix can have an effect on the inversion operation. A better embodiment can be provided in such a way that all columns of the P matrix are orthogonal to one another. In other words, in some embodiments it may be better to choose P _k tone by tone arbitrarily. In each example, the P _k design on the receiving wireless communication device (eg, STA) must be known. A larger CSD value can be used in Dk, which varies more tone by tone. CSD values are also specified in the IEEE 802.11 specification, but additional CSD values can be added in the diagonal Q matrix. In such an embodiment, Q _k can be generated via a Fast Fourier Transform (FFT) matrix or a Hadamard matrix and the cyclic shifting can be implemented tone by tone. An iterative design can be used and the value of y _k can be reconstructed from the estimated channel and then used to re-estimate h _k .

10 illustrates an embodiment 1000 of a performance or performance diagram with a spatial channel model (SCM: “spatial channel model”) at 900 MHz (31.25 kHz). In particular, an example of a 4x1 channel configuration for three different CSD values with a grouping of 8 tones is shown. 11 illustrates an embodiment 1100 of another performance diagram for a 3x1 channel configuration using an FFT-Q matrix with groupings of either 4 or 8 tones. 12 illustrates an embodiment 1200 of another performance diagram for a 4x1 channel configuration for a grouping of 8 tones and either an FFT-Q matrix or a Hadamard-Q matrix. As shown in these examples, this shortened form of channel estimation achieves a channel estimation error that is better than -5 dB MSE. In some embodiments, smaller groupings can help make the assumption (h _ikj = h _ikm ) more realistic, but the P matrix can also have a larger number of conditions. Under certain circumstances, this technique can perform better than a CSD-D _k matrix.

13 An embodiment 1300 of a performance diagram illustrates the effect of CSD channel estimation on phase-aligned space-time block coding ( STBC ) shows. While not expressly shown, similar effects are achieved in an output signal-to-noise ratio (SNR) with an SCM signal. As will be understood, performing channel estimation in this manner avoids any need to send an NDP frame for channel estimation only. A regular data packet (with a single stream) can be used to estimate the Nt × 1 channel sufficiently accurately to obtain the phase information for a phase-aligned STBC. Piggybacking phase-only feedback information in an Nt × 1 system within an ACK frame can achieve a significant amount of feedback overhead savings. This phase-only feedback can only be 2 bits / tone for an 8-tone grouping, without having a significant impact on the channel quality estimate. The information bits required to transmit such phase-only feedback for the 2 MHz band are only 13 information bits. The impact of additional 13 bits (2 bytes) on throughput is negligible.

14 illustrates an embodiment 1400 of providing feedback (FB) information using ACK (eg, a combined ACK and FB exchange). In particular, a communication exchange between two communication devices is shown, such as an access point ( AP ), a station (STA), or other devices such as those related to 1 to 13 and in particular devices employing one or more of the channel estimation techniques described above. In operation, a transmitter of one device sends a first signal to the receiver of another device, which is a data frame 1402 with a phase feedback request, such as clue data in a signal (SIG) field of the data frame. In response to this request, a baseband processor of the receiving device generates phase feedback information based on a channel estimate of a wireless communication channel between the two communication devices according to the channel estimation techniques described above. A transmitter of the receiving device transmits an acknowledgment (ACK) frame 1404 to the other device in response to the data frame 1402 , The ACK frame 1404 includes the phase feedback information.

In one embodiment, the data frame is 1402 a single data frame with a single long training field and a non-zero data payload. The baseband processor of the receiving device generates the channel estimate from or based on an analysis of this individual data frame - and not based on a zero data packet ( NDP ). As discussed above, the baseband processor can generate the channel estimate based on a diagonal matrix of cycled delay or other CSD data.

As can be seen with reference to the illustration, a combined ACK with phase feedback information (a "FACK" frame) can be transmitted. This can allow a relatively simple frame format with the addition of only a few bytes in the acknowledgment frame, such as three or fewer bytes of phase feedback information (MgmtActionFB). While the phase feedback is described above as being included in an acknowledgment frame, such as via a modified acknowledgment frame format, other alternatives can be used to convey the requested phase feedback information back to the requesting communication device. Other alternatives may allow the phase feedback information to be formatted either in a special frame format other than an acknowledgment frame or in a combined frame format that includes the acknowledgment frame. For example, the receiving device ACK and MgmtActionFB can each transmit as separate frames. With regard to the SIFS + PHY header, a MAC header should also be used. There can be various considerations regarding TXOP control (e.g., that the TXOP holder expects a sender to insert SIFS after ACK). Other alternatives may allow the use of a unified MAC (Media Access Control) protocol data unit with ACK + MgmtActionFB (A-MPDU). Some considerations include the overhead of A-MPDU density and many bytes in the management frame (e.g. MAC header bytes).

It should be noted that although the phase feedback requirement is discussed above as clue data in the signal (SIG) field of the data frame, other clues can be used. In another example, the phase feedback request can be made through clue data in the PHY payload portion of the frame. Other locations in the data frame can also be used to carry a phase feedback request, including other header and payload parts, and / or other layers of the protocol stack.

15 illustrates an embodiment 1500 of a FACK frame format. Such a FACK frame can be effective to use one of reserved control sub-types, e.g. 0000-0110. FB_INFO is variable depending on the bandwidth. The bandwidth ( BW ) is referred to in the frame. The PHY utility with MCS0 is (in the case of BW = 20 MHz) 5 to (in the case of BW = 160 MHz) 9-ODFM symbols, the original ACK being 5 ODFM symbols.

With 8 OFDM symbols from a PHY preamble, the send time for an old ACK = 52 µsec at 802.11n / ac, and the send time for FACK becomes approximately 52 µsec (in the case of BW = 20 MHz) to 68 µsec (in the case BW = 160 MHz) at 802.11n / ac. The first three fields still conform to IEEE 802.11 protocol version = 00b.

With respect to a data DUR field calculation, the feedback size in a FACK frame is known since the bandwidth (BW) of a data frame is known. Therefore, the size of FACK can be predicted exactly. The DUR field value of a data frame can also be assigned precisely.

With regard to considering when to send an angular feedback, a sending wireless communication device (e.g. AP . AP working as STA, etc.) to send an indication that it wants feedback with phase-only information.

Use of one bit in the PHY signal field can be performed. For example, such an operation can be done using FACK_REQ = FACK request. Ideally, a receiving wireless communication device (e.g., STA, etc.) or a responding communication device can respond with FACK, but ACK is acceptable because, at worst, DUR / NAV will exceed what is needed by a small amount.

In many cases, depending on the feedback size and MSC of FACK or ACK, FACK and ACK will have the same number of symbols anyway. For some cases, FACK will be longer than ACK, and if the receiving wireless communication device requesting FACK_REQ (e.g. STA, etc.) has calculated DUR based on a FACK response, NAV may be a little too large. This is not a serious problem, so the selection of a response is left to the receiving wireless communication device (e.g., STA, etc.) or the answering communication device.

A new framework is proposed here (e.g. a new FACK framework) that (phase-only or phase-pure) feedback information, the length of which is only a few bytes (for example 2 to 14 bytes, depending on the bandwidth). Such phase-only information from an Nt × 1 channel can be obtained by an Ng tone grouping, assuming that the channel is fairly flat from the transmission of a single stream packet (with an LTF). The channel estimation quality of the proposed model shows only a marginal deterioration in performance or performance (0 to 1 dB) with respect to the phase-aligned STBC model. As can be understood, this does not require any additional exploratory framework exchange (e.g. NDP ) and only a few additional bytes of information, which is why the impact on overhead or additional effort is negligible.

It is also noted that the various operations and functions as described with respect to various methods herein may be performed in a wireless communication device, such as using a baseband processing module and / or processing module implemented therein (e.g., such as in accordance with the baseband processing module 64 and / or the processing module 50 as it is referring to 2 ) and / or other components therein, including one or more baseband processing modules, one or more media access control (MAC) layers, one or more physical layers (PHYs) and / or other components, etc. For example, a baseband processing module may include such Generate signals and frames as described herein, as well as perform various operations and analyzes as described herein, or perform any other operations and functions as described herein, etc., or their respective equivalents.

In some embodiments, such a baseband processing module and / or processing module (which may be implemented in the same device or separate devices) may perform such processing to transmit signals using at least one of any number of radio units and at least one of any Generate number of antennas to another wireless communication device (e.g., which may also include at least any number of radio units and at least any number of antennas) according to various aspects of the invention, and / or any other operations and functions as described herein are described, etc., or perform their respective equivalents. In some embodiments, processing is performed cooperatively by a processing module in a first device and a baseband processing module in a second device. In other exemplary embodiments, such processing is carried out entirely by a baseband processing module or a processing module.

When used herein, the terms "substantially" and "approximately" provide a commercially acceptable tolerance for their corresponding term and / or relativity between elements. Such a commercially accepted tolerance ranges from less than one percent to fifty percent and corresponds to, but is not limited to, component values, process variations in integrated circuits, temperature variations, rise and fall times, and / or thermal noise. Such relativity between elements ranges from a difference of a few percent to larger differences. As can also be used herein, the terms "operationally coupled", "coupled" and / or "coupling" include a direct coupling between objects and / or an indirect coupling between objects via an object in between (whereby an object comprises, for example, but is not limited to, a component, an element, a circuit and / or a module), wherein for an indirect coupling the object in between does not modify the information of a signal, but does adapt its current level, voltage level and / or energy / power level can. As further used herein, an inference-based coupling (ie, where one element is coupled to another by inference) includes direct and indirect coupling between two objects in the same way as "coupled". As may be used further herein, the term "operable" or "operatively coupled" means that an object includes one or more of the following: power connections, input (s), output (s), etc., to when it is enabled to perform one or more of its corresponding functions, and it may further include inference-based coupling to one or more other objects. As may be used further herein, the term "in connection with" includes a direct and / or indirect coupling of separate objects and / or an object that is embedded in another object. As used herein, the term "positive comparison" means that a comparison between two or more objects, signals, etc. provides a desired relationship. For example, if the desired relationship is that signal 1 has a larger amount than signal 2 , a positive comparison can be made if the amount of signal 1 is larger than that of signal 2 , or if the amount of signal 2 is smaller than that of signal 1 ,

As may also be used herein, the terms "processing module", "module", "processing circuit", and / or "processing unit" (eg, encompassing various modules and / or circuits, such as those that are operational, implemented, and / or can be provided for coding, for decoding, for baseband processing, etc.) represent a single processing device or a multiplicity of processing devices. Such a processing device can be a microprocessor, a microcontroller, a digital signal processor, a microcomputer, a central processing unit, a field programmable gate array, a programmable logic device, a state machine, a logic circuit, an analog circuit, a digital circuit and / or any device be that manipulates or processes (analog and / or digital) signals based on a fixed coding of the circuit and / or operating instructions. The processing module, the module, the processing circuit and / or the processing unit can have an associated memory and / or an integrated memory element which comprises a single memory device, a multiplicity of memory devices and / or an embedded circuit of the processing module, the module, the processing circuit and / or the processing unit. Such a storage device can be a read-only memory ( ROME ), a random access memory ( R.A.M. ), volatile memory, non-volatile memory, static memory, dynamic memory, flash memory, cache memory and / or any device that stores digital information. It should be noted that if the processing module, the module, the processing circuit and / or the processing unit comprises more than one processing device, the processing devices are arranged centrally (e.g. directly coupled to one another via a wired and / or wireless bus structure) or distributed (e.g. via cloud computing via an indirect coupling via a local area network and / or a wide area network). It should also be noted that if the processing module, module, processing circuit and / or processing unit implements one or more of its functions via a state machine, an analog circuit, a digital circuit and / or a logic circuit, the memory and / or the memory element which stores the corresponding operating instructions can be embedded in or external to the circuit which has the state machine, the analog circuit, the digital circuit and / or the logic circuit. It should also be noted that the memory element can store hard-coded and / or operational instructions that correspond to at least some of the steps and / or functions illustrated in one or more of the figures, and the processing module, the module, the processing circuit and / or the processing unit executes them. Such a storage device and / or such a storage element can be included in a production / product.

The present invention has been described above with the aid of process steps that illustrate the operational characteristics of specific functions and relationships thereof. The delimitation and sequence of these functional components and method steps have been defined here for the sake of simplicity of description. Alternative demarcations and sequences can be defined as long as the specified functions and relationships are carried out in an appropriate manner. All such alternative delimitations or sequences are therefore within the scope and spirit of the claimed invention. Furthermore, the boundaries of these functional building blocks have been arbitrarily defined for the sake of simplicity of description. Alternative demarcations can be defined as long as the certain relevant functions are carried out in an appropriate manner. Likewise, flowchart blocks may have been arbitrarily defined herein to illustrate a particular authoritative functionality. To or to the extent used, boundaries and sequences of the flowchart blocks could have been defined differently and continue to carry out the specific relevant functionality. Such alternative definitions of both functional building blocks and flowchart blocks and sequences are therefore within the scope and idea of the claimed invention. One skilled in the art will also recognize that the functional building blocks and other illustrative blocks, modules, and components may be implemented herein, as illustrated, or by discrete components, application specific integrated circuits, processors that execute appropriate software, and the like, or any combination can be implemented by these.

The present invention has been described, at least in part, with respect to one or more embodiments. An embodiment of the present invention is used herein to illustrate the present invention, an aspect thereof, a feature thereof, a concept thereof, and / or an example thereof. A physical embodiment of an apparatus, fabrication, machine, and / or process embodying the present invention may include one or more of the aspects, features, concepts, examples, etc., which may be described with reference to an or several of the embodiments discussed herein are described. Furthermore, the embodiments from figure to figure may include the same or similarly named functions, steps, modules, etc., which may have the same or different reference numerals, and as such, the functions, steps, modules, etc. may have the same or similar functions , Steps, modules, etc. or different.

Unless specifically stated otherwise, signals to, from and / or between elements in a figure from any of the figures shown here can be analog or digital, continuous or discrete-time and simple (or unbalanced or single or one-sided (grounded) ) or be differential. For example, if the signal path is shown as a simple path, a signal path also represents a differential signal path. Likewise, if the signal path is shown as a differential path, a signal path also represents a simple signal path. While one or more particular architectures herein other architectures may also be implemented using one or more data buses, not specifically shown, using direct connectivity between elements and / or indirect coupling between other elements, as will be recognized by one skilled in the art.

The term "module" is used in the description of the various embodiments of the present invention. A module includes a function block implemented by hardware to perform one or more module functions, such as processing one or more input signals to produce one or more output signals. The hardware that implements the module can even work in conjunction with software and / or firmware. As used herein, a module can include one or more sub-modules that are themselves modules.

While certain combinations of various functions and features of the present invention have been expressly described herein, other combinations of these features and functions are equally possible. The present invention is not limited by the particular examples disclosed herein, and expressly encompasses these other combinations.

A device includes a receiver for receiving a first signal from at least one other device that includes a data frame that includes a FACK request in a signal (SIG) field. A baseband processor generates feedback information for use in performing channel estimation. A transmitter sends a second signal, which includes the feedback information, to the at least one further device.

Claims (20)

Device with: a receiver for receiving a first signal from at least one other device comprising a data frame, the data frame comprising a phase feedback request; a baseband processor, coupled to the receiver, that generates phase feedback information; a transmitter coupled to the baseband processor that sends an acknowledgment (ACK) frame to the at least one other device in response to the data frame, the ACK frame including the phase feedback information. Device according to Claim 1 wherein: the baseband processor generates the phase feedback based on a channel estimate of a wireless communication channel between the device and the at least one other device. Device according to Claim 2 , wherein: the data frame is a single data frame and the baseband processor generates the channel estimate from an analysis of the single data frame. Device according to Claim 2 wherein: the baseband processor generates the channel estimate based on a diagonal matrix of cyclically shifted delay. Device according to Claim 2 where: the data frame comprises a single long training field. Device according to Claim 1 wherein: the data frame includes the phase feedback request in one of: a signal (SIG) field of the data frame and a payload portion of the physical layer of the data frame. Device according to Claim 1 wherein: the data frame comprises a non-zero data payload. Device according to Claim 1 wherein: the phase feedback information comprises less than three bytes of data. Device according to Claim 1 wherein: the device is a wireless station (STA); and the at least one further device is an access point (AP). Device according to Claim 1 wherein: the device is an access point (AP); and the at least one other device is a wireless station (STA). Device with: a transmitter for sending a first signal to at least one further device comprising a data frame, the data frame comprising a request for phase feedback; a receiver for receiving an acknowledgment (ACK) frame from the at least one other device in response to the data frame, the ACK frame comprising phase feedback information generated by the at least one other device. Device according to Claim 11 , wherein: a baseband processor of the at least one further device generates the phase feedback based on a channel estimate of a wireless communication channel between the device and the at least one further device. Device according to Claim 12 , wherein: the data frame is a single data frame and the baseband processor generates the channel estimate from an analysis of the single data frame. Device according to Claim 12 wherein: the baseband processor generates the channel estimate based on a diagonal matrix of cyclically shifted delay. Device according to Claim 12 where: the data frame comprises a single long training field. Device according to Claim 11 wherein: the data frame includes the phase feedback request in one of: a signal (SIG) field of the data frame and a payload portion of the physical layer of the data frame. Device according to Claim 11 wherein: the data frame comprises a non-zero data payload. Device according to Claim 11 wherein: the phase feedback information comprises less than three bytes of data. Device with: a receiver for receiving a first signal from at least one other device comprising a single data frame, the single data frame comprising a phase feedback request and a single long training sequence; a baseband processor, coupled to the receiver, that generates phase feedback information based on a channel estimate of a wireless communication channel between the device and the at least one further device based on an analysis of the single data frame, comprising generating a cyclically shifted delay matrix; and a transmitter, coupled to the baseband processor, that sends phase feedback information to the at least one other device in response to the data frame. Device according to Claim 19 wherein: the phase feedback information is transmitted via one of: an acknowledgment frame, a feedback frame, and a merged frame.

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