US20150180921A1 - Signaling to application lack of requested bandwidth - Google Patents

Signaling to application lack of requested bandwidth Download PDF

Info

Publication number
US20150180921A1
US20150180921A1 US14/562,470 US201414562470A US2015180921A1 US 20150180921 A1 US20150180921 A1 US 20150180921A1 US 201414562470 A US201414562470 A US 201414562470A US 2015180921 A1 US2015180921 A1 US 2015180921A1
Authority
US
United States
Prior art keywords
digital data
computing device
data stream
modulated
subchannels
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Abandoned
Application number
US14/562,470
Inventor
Amer A. Hassan
Thomas W. Kuehnel
Deyun Wu
Christian Huitema
D. Gabriel Frost
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Microsoft Technology Licensing LLC
Original Assignee
Microsoft Technology Licensing LLC
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority to US11/433,804 priority Critical patent/US8189621B2/en
Priority to US13/452,637 priority patent/US8923340B2/en
Application filed by Microsoft Technology Licensing LLC filed Critical Microsoft Technology Licensing LLC
Priority to US14/562,470 priority patent/US20150180921A1/en
Assigned to MICROSOFT TECHNOLOGY LICENSING, LLC reassignment MICROSOFT TECHNOLOGY LICENSING, LLC ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: MICROSOFT CORPORATION
Assigned to MICROSOFT CORPORATION reassignment MICROSOFT CORPORATION ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: FROST, D. GABRIEL, HASSAN, AMER A., HUITEMA, CHRISTIAN, KUEHNEL, THOMAS W., WU, DEYUN
Publication of US20150180921A1 publication Critical patent/US20150180921A1/en
Application status is Abandoned legal-status Critical

Links

Images

Classifications

    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04WWIRELESS COMMUNICATION NETWORKS
    • H04W28/00Network traffic or resource management
    • H04W28/02Traffic management, e.g. flow control or congestion control
    • H04W28/0268Traffic management, e.g. flow control or congestion control using specific QoS parameters for wireless networks, e.g. QoS class identifier [QCI] or guaranteed bit rate [GBR]
    • HELECTRICITY
    • H03BASIC ELECTRONIC CIRCUITRY
    • H03MCODING; DECODING; CODE CONVERSION IN GENERAL
    • H03M1/00Analogue/digital conversion; Digital/analogue conversion
    • H03M1/12Analogue/digital converters
    • HELECTRICITY
    • H03BASIC ELECTRONIC CIRCUITRY
    • H03MCODING; DECODING; CODE CONVERSION IN GENERAL
    • H03M9/00Parallel/series conversion or vice versa
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04LTRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L27/00Modulated-carrier systems
    • H04L27/18Phase-modulated carrier systems, i.e. using phase-shift keying includes continuous phase systems
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04LTRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L27/00Modulated-carrier systems
    • H04L27/26Systems using multi-frequency codes
    • H04L27/2601Multicarrier modulation systems
    • H04L27/2602Signal structure
    • H04L27/2605Symbol extensions
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04LTRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L27/00Modulated-carrier systems
    • H04L27/26Systems using multi-frequency codes
    • H04L27/2601Multicarrier modulation systems
    • H04L27/2602Signal structure
    • H04L27/2605Symbol extensions
    • H04L27/2607Cyclic extensions
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04LTRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L27/00Modulated-carrier systems
    • H04L27/32Carrier systems characterised by combinations of two or more of the types covered by groups H04L27/02, H04L27/10, H04L27/18 or H04L27/26
    • H04L27/34Amplitude- and phase-modulated carrier systems, e.g. quadrature-amplitude modulated carrier systems
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04LTRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L5/00Arrangements affording multiple use of the transmission path
    • H04L5/003Arrangements for allocating sub-channels of the transmission path
    • H04L5/0053Allocation of signaling, i.e. of overhead other than pilot signals
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04LTRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L5/00Arrangements affording multiple use of the transmission path
    • H04L5/003Arrangements for allocating sub-channels of the transmission path
    • H04L5/0058Allocation criteria
    • H04L5/006Quality of the received signal, e.g. BER, SNR, water filling
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04LTRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L5/00Arrangements affording multiple use of the transmission path
    • H04L5/003Arrangements for allocating sub-channels of the transmission path
    • H04L5/0058Allocation criteria
    • H04L5/0064Rate requirement of the data, e.g. scalable bandwidth, data priority
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04LTRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L5/00Arrangements affording multiple use of the transmission path
    • H04L5/14Two-way operation using the same type of signal, i.e. duplex
    • H04L5/1438Negotiation of transmission parameters prior to communication
    • H04L5/1446Negotiation of transmission parameters prior to communication of transmission speed
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04LTRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L65/00Network arrangements or protocols for real-time communications
    • H04L65/40Services or applications
    • H04L65/4069Services related to one way streaming
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04LTRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L65/00Network arrangements or protocols for real-time communications
    • H04L65/80QoS aspects
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04WWIRELESS COMMUNICATION NETWORKS
    • H04W28/00Network traffic or resource management
    • H04W28/16Central resource management; Negotiation of resources or communication parameters, e.g. negotiating bandwidth or QoS [Quality of Service]
    • H04W28/24Negotiating SLA [Service Level Agreement]; Negotiating QoS [Quality of Service]

Abstract

A system for signaling an application when a requested data rate and Quality of Service cannot be achieved using OFDM wireless data transmission, and the application proceeds by either renegotiating QoS and data rate, or waiting until they requested rate and QoS are met.

Description

    RELATED APPLICATIONS
  • This Application is a Continuation of and claims benefit from U.S. patent application Ser. No. 13/452,637 that was filed Apr. 20, 2012, and that is a Continuation of U.S. application Ser. No. 11/433,804 (U.S. Pat. No. 8,189,621 issued May 29, 2012), that was filed on May 12, 2006, each of which is incorporated herein by reference in its entirety.
  • BACKGROUND OF INVENTION
  • 1. Field of Invention
  • The invention relates generally to wireless communication and more particularly to a system for notifying a communication application that a requested data rate and quality of service are not available.
  • 2. Discussion of Related Art
  • Frequency Division Multiplexing (FDM) is a well known process by which multiple signals are modulated on different frequency carrier waves. FDM has been used for decades in radio and television broadcast. Radio and television signals are sent and received on different frequencies, each corresponding to a different “channel.”
  • Orthogonal Frequency Division Multiplexing (OFDM) has also been known in the art at least since the late 1960's. In OFDM, a single transmitter transmits simultaneously on many different orthogonal frequencies. Orthogonal frequencies are frequencies that are independent with respect to the relative phase relationship between the frequencies. In OFDM, the available bandwidth is subdivided into a number of equal-bandwidth “subchannels.” OFDM is advantageous for wireless communication because it has robust performance in multipath fading. In general, OFDM based systems do not require an equalizer for reliable communications. OFDM is employed in many standards used today for wireless communication. For example, both the IEEE 802.11a wireless LAN Standard and the 802.11 wireless LAN standard rely on an implementation of OFDM for signal transmission. The next generation 802.11n wireless LAN Standard, UWB wireless PAN Standard, and mobile WiMAX all use OFDM modulation for high rate communications. One early reference describing OFDM is R. W. Chang, Synthesis of band-limited orthogonal signals for multi-channel data transmission, Bell System Technical Journal (46), 1775-1796 (1966).
  • OFDM thus functions by breaking one high speed data stream into a number of lower-speed data streams, which are then transmitted in parallel simultaneously). Each lower speed stream is used to modulate a subcarrier. This creates a “multi-carrier” transmission by dividing a wide frequency band (or channel) into a number of narrower frequency bands (or subchannels), each modulated with a signal stream. By sending multiple signal streams simultaneously, each at a lower rate, multipath or Raleigh fading can be reduced or eliminated without decreasing the overall rate of transmission.
  • OFDM is also implemented in a variety of communications systems occurring over wires. For example, OFDM is used in Asymmetric Digital Subscriber Line (ADSL) connections that adhere to the ITU 0.992.1 standard. In the ADSL context, OFDM is sometimes referred to as Discrete Multitone Modulation, or DMT. OFDM is also often used to modulate signals to be transmitted over power wires. For example, the HomePlug powerline alliance established a standard for communication over power lines in a home. The HomePlug standard uses OFDM modulation.
  • Over the past several years, numerous network applications have come into common use that require certain transmission characteristics to work effectively. For example, Voice-over-IP (VoIP) communication, also known as IP Telephony, Internet Telephony, or Broadband Phone, is a telephone-like system that works entirely or partially over the Internet by converting a voice signal into a digital signal that can be transmitted in Internet packets. VoIP traffic requires a minimum data transfer rate to be useable for communication. Similarly, the transmission of video content (for example, video teleconferencing or streaming multimedia) over a network typically requires certain minimum transmission characteristics to be viewable.
  • When the Internet was first created, there were no systems in place to insure minimum transmission characteristics. Over time, standards for Quality of Service (QoS) have developed to provide guaranteed transmission characteristics such as minimum performance or throughput, or maximum latency. QoS can be implemented within a local network or over a broader area. One reference discussing QoS is the IEEE 802.1p standard, which is implemented at the media access control (MAC) framing layer on the protocol stack.
  • SUMMARY OF INVENTION
  • This Summary provides an illustrative context for aspects of the invention, in a simplified form. It is not intended to be used to determine the scope of the claimed subject matter. Aspects of the invention are described more fully below in the Detailed Description.
  • Described herein are systems and methods for selecting OFDM transmission parameters based on a data rate and Quality of Service requested by an application and signaling to the application if the requested data rate and Quality of Service are not possible. The requested data rate and Quality of Service are mapped to a set of communications parameters, noise level on the OFDM subchannels is detected and the application receives a signal if the communication parameters cannot be achieved given the noise conditions on the OFDM subchannels. The application can then decide whether it will renegotiate its requested data rate and Quality of Service, or wait until such request can be accommodated by the channel.
  • BRIEF DESCRIPTION OF DRAWINGS
  • The accompanying drawings are not intended to be drawn to scale. In the drawings, each identical or nearly identical component that is illustrated in various figures is represented by a like numeral. For purposes of clarity, not every component may be labeled in every drawing. In the drawings:
  • FIG. 1 is a spectrum diagram showing the subdivision of the channel bandwidth to be used into several subchannels of equal width.
  • FIG. 2 is a block diagram of a multi-carrier OFDM digital communication system.
  • FIG. 3 is a flow diagram illustrating the selection by an application of a data rate and a Quality of Service.
  • FIG. 4 is a flow diagram illustrating one embodiment of the invention.
  • FIG. 5 is a flow diagram illustrating some aspects of the invention.
  • FIG. 6 is a flow diagram illustrating a system implementing some aspects of the invention.
  • DETAILED DESCRIPTION
  • This invention covers a novel method for wireless communication. According to the claimed invention, an application requests a data rate and Quality of Service. The system determines the number of subchannels, the quality of the subchannels, and the power for transmission on the subchannels necessary to achieve the requested data rate and QoS. If the transmission environment is such that the selected parameters are not achievable, the system can either modify the selected parameters or signal to the application through the stack that the requested service is not possible. The invention may be implemented in hardware or software, or some combination thereof. Software implementations, for example, could be in the operating system or in a device driver. Embodiments include a system, a method, and instructions stored in a computer-readable medium.
  • Computer readable media can be any available media that can be accessed by a computer. By way of example, and not limitation, computer readable media may comprise computer storage media and communication media. Computer storage media includes volatile and nonvolatile, removable and non-removable media implemented in any method or technology for storage of information such as computer readable instructions, data structures, program modules or other data. Computer storage media includes, but is not limited to, RAM, ROM, EEPROM, flash memory or other memory technology, CD-ROM, digital versatile disks (DVD) or other optical storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, other types of volatile and non-volatile memory, any other medium which can be used to store the desired information and which can accessed by a computer, and any suitable combination of the foregoing.
  • The computer-readable media may be transportable such that the instructions stored thereon can be loaded onto any suitable computer system resource to implement the aspects of the present invention discussed herein. In addition, it should be appreciated that the instructions stored on the computer-readable medium, described above, are not limited to instructions embodied as part of an application program running on a host computer. Rather, the instructions may be embodied as any type of computer code (e.g., software or microcode) that can be employed to program a processor to implement the aspects of the present invention discussed below.
  • This invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways. Also, the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of “including,” “comprising,” or “having,” “containing,” “involving,” and variations thereof herein, is meant to encompass the items listed thereafter and equivalents thereof as well as additional items.
  • The invention may be embodied in either a wired OFDM communication system or a wireless OFDM communication system.
  • As shown in FIG. 1, in OFDM, the available channel bandwidth W is subdivided into a number of equal-bandwidth subchannels. Each subchannel is sufficiently narrow so that the frequency response characteristics of the subchannel are nearly ideal. The number of subchannels is the total available bandwidth divided by the bandwidth of each subchannel. The number of subchannels K can thus be expressed as:
  • K = W Δ f
  • Each subchannel k has an associated carrier wave. This carrier wave can be expressed as:

  • x k(t)=sin 2πf k t
  • Where xk(t) is the carrier wave for subchannel k as a function of time t. fk is the mid-frequency of subchannel k, and k ranges from 0 to K−1. The phase of xk(t) is set to zero without losing generality.
  • The symbol rate 1/T is set for each subchannel to be equal to the separation Δf of adjacent subcarriers. The subcarriers will thus be orthogonal over the symbol interval T, independent of the relative phase relationship between subcarriers. This relationship can be expressed as:
  • 0 T sin ( 2 π f k t + φ k ) sin ( 2 π f j t + φ j ) t = 0
  • Where fk−fj=n/T, n=1, 2, . . . , independent of the values of the (arbitrary) phases Φk and Φj.
  • In an OFDM system, the symbol rate on each subchannel can be reduced relative to the symbol rate on a single carrier system that employs the entire bandwidth W and transmits data at the same rate as the OFDM system. Hence, the symbol interval T (the inverse of the symbol rate) in the OFDM system can be expressed as:

  • T=KT s
  • where Ts is the symbol interval of a single-carrier system employing the entire bandwidth W and transmitting data at the same rate as the OFDM system. For example, if the symbol rate across the entire bandwidth for one channel is 72 million symbols per second, and the channel is divided into 48 subchannels, each subchannel would only need to carry 1.5 million symbols per second to achieve the same total data rate. This lower symbol rate reduces inter-symbol interference and thus mitigates the effects of multipath fading. Accordingly, OFDM provides for superior link quality and robustness of communication.
  • In an OFDM system, the transmitter receives input data in the frequency domain and converts it to a time domain signal. A carrier wave is modulated by the time domain signal for wireless transmission or transmission over a wire. The receiver receives the signal, demodulates the wave, and converts the signal back to the frequency domain for further processing.
  • A simplified OFDM system is illustrated in FIG. 2, In the illustrated embodiment, the input data stream 201 is provided by the application to the OFDM transmitter 200, In a standard TCP/IP communications stack, this data could be received at the physical layer or data link layer; however, the invention is not limited to any particular source of data or mechanism for providing the data to the transmitter, and could be implemented in hardware or software, and at various layers of the network stack. The input data stream 201 is received by a serial-to-parallel buffer 202. The serial-to-parallel buffer 202 breaks the serial data stream up into several parallel data streams. The number of parallel data streams is equal to the number of subchannels available for OFDM broadcast, or K as used above.
  • In one embodiment, the serial-to-parallel buffer 202 divides the information sequence received from input data 201 into frames of Bf bits. The Bf bits in each frame are parsed into K groups, where the ith group is assigned bi bits. This relationship may be expressed as:
  • i = 1 K b i = B f
  • Each of the parallel data streams generated by the serial-to-parallel buffer 202 is then sent to a multicarrier modulator 203. The multicarrier modulator 203 modulates each OFDM subcarrier with each of the parallel data streams. The multicarrier modulator 203 can be efficiently implemented by use of the Inverse Fast Fourier Transform (IFFT) algorithm to compute the time domain signal, although any algorithm may be used that converts a frequency domain signal to a time domain signal, Fast FFF algorithms have been the subject of research for decades, and there are numerous low complexity implementations that facilitate the implementation of OFDM systems.
  • The multicarrier modulator 203 may use any modulation scheme to modulate each of the incoming data streams. In preferred embodiments, the signals are modulated with phase shift keying (PSK) modulation, or quadrature amplitude modulation (QAM). Any PSK or OAM constellation may be used, such as those used in the wireless LAN family of standards, including 802.11a, 802.11g, and 802.11n. For example, the modulator may use 8PSK, 16-QAM, 64-QAM, 128-QAM or 256-QAM. A modulation scheme may be selected based on the required data rate, the available subchannels, the noise on each subchannel, or other factors.
  • In this example, the multicarrier modulator 203 thus generates K independent QAM subchannels, where the symbol rate for each subchannel is 1/T and the signal in each subchannel has a distinct QAM constellation. According to this example, the number of signal points for the ith subchannel can be expressed as:

  • M i=2b i
  • The complex-valued signal points corresponding to the information signals on each of the K subchannels can be represented as Xk, where k=0, 1, . . . , K−1. These symbols Xk represent the values of the Discrete Fourier Transform (DFT) of a multicarrier OFDM signal x(t), where the modulation on each subcarrier is QAM. Since x(t) must be a real-valued signal, its N-point DFT Xk must satisfy the symmetry property. Therefore, the system Creates N=2K symbols from K information symbols by defining:

  • X N-K =X′ K , k=1, 2, . . . , K−1

  • X′=Re(X 0)

  • X N =Im(X 0)
  • Here X0 is split into two parts, both of which are real. The new sequence of symbols can be expressed as X′k, where k=0, 1, . . . N−1, The N-point Inverse Direct Fourier Transform for each subchannel xn can thus be expressed as:
  • x n = 1 N k = 0 N - 1 X k exp ( j 2 π nk / N ) n = 0 , 1 , , N - 1
  • in this equation,
  • 1 N
  • is a scale factor. The sequence xn where 0<=n<=N−1 thus corresponds to samples of the multicarrier OFDM signal x(t), consisting of K subcarriers.
  • A cyclic prefix, which acts a guard interval, is added to each of the parallel modulated waves at 204. This guard interval insures that the subchannels will remain orthogonal, even if multipath fading causes the subcarriers to arrive at the receiver with some delay spread. The parallel streams with the cyclic prefix are then merged back into a single serial stream at 204. Finally, the digital data stream is converted to an analog signal 205, and output for wireless transmission.
  • The transmitted signal can be received by the receiver 210 and processed to recover the original data stream. First, the analog signal is converted back to a digital signal by an analog to digital converter 211. The cyclic prefix is removed and the separate subcarriers are converted back to separate streams at 212. Each parallel data stream is demodulated by a multicarrier demodulator 213, preferably with a Fast Fourier Transform (FFT) algorithm. Finally, at 214 the parallel streams are reassembled into a single serial stream and output to the receiving device 215.
  • As illustrated in FIG. 3, in one embodiment, an application 301 requests a data rate 302 and a Quality of Service 303. The application 301 can be any network application, including, for example, a Voice-over-IP client or a streaming video application. The data rate 302 and Quality of Service 303 requested by the application 301 may depend on the nature of the content to be transmitted. For example, high-definition video requires a higher data rate than simple voice or text communication. Voice-over-IP requires that latency or delay be less than a certain maximum amount. Communications relating to emergency services may require a very low error rate and high priority of transmission.
  • The requested data rate 302 is the data rate appropriate for the application 301, For example, a high definition video application could request a data rate of 22 Mbps, while an instant messenger client transmitting only text could request a much lower data rate.
  • Similarly, the Quality of Service 303 is the Quality of Service appropriate for the application 301. The Quality of Service can be any set of communications parameters, including, for example, parameters relating to performance, throughput, or latency. The IEEE 802.1p standard provides one example of a set of Quality of Service parameters, Under the WEE 802.1p standard the following parameters are essential for providing a Quality of Service:
      • Service Availability
      • Frame loss
      • Frame missorder
      • Frame duplication
      • The transit delay experienced by frames
      • Frame lifetime
      • The undetected frame error rate
      • Maximum service data unit size, supported
      • User priority
      • Throughput
  • Under the IEEE 802.1Q standard, the requested, QoS is set to a value between 0 and 7. Each such value corresponds to a delay and probability of error. In other embodiments, an in-band protocol header contains the QoS. For example, Differentiated Services Code Point (DSCP) is stored in the Type of Service (TOS) field in the IPv4 protocol header and in the Traffic Class field in the IPv6 header. A network can be configured such that DSCP-marked traffic can have differentiated levels of service. In another embodiment, the QoS may be encoded in an out-of-band state variable, According to the claimed, invention, any method may be used for requesting a QoS.
  • FIG. 4 illustrates the steps taken in one embodiment in response to an is application's request thr a particular data rate and Quality of Service. In the discussion of FIG. 4, the steps described are implemented, on a transmitter. The transmitter could be part of a network card, a device driver, or a component of an operating system. The invention is not limited to any particular implementation of a transmitter, whether hardware or software.
  • In the embodiment illustrated in FIG. 4, the application 401 requests a data rate R and a Quality of Service q. The network interface card (NIC) or wireless standard may have a minimum transfer rate Rmin, a maximum transfer rate Rmax, or both. For example, the following maximum rates apply to various IEEE 802.11 wireless standards:
  • Wireless Standard Rmax 802.11b  6 Mbps 802.11a  26 Mbps 802.11n (20 MHz) 100 Mbps 082.11n (40 MHz) 200 Mbps
  • At 402, if Rmin or Rmax is defined for the NIC or wireless standard, the transmitter checks if the requested data rate R is between Rmin and Rmax. This test can be expressed mathematically as:

  • R min ≦R≦R max
  • If R is not an acceptable value, the transmitter can either signal to the application that the requested service is not possible at 403, or select another data rate at 404. The data rate selected at 404 may be the closest data rate to the requested data rate that is within the acceptable range Rmin to Rmax.
  • If the requested data rate R is an acceptable value, at 405 the transmitter maps the requested data rate R and the requested QoS q to a number of OFDM subchannels K and a maximum energy level for each of those subchannels E. The number of subchannels K and maximum energy level E must be sufficient to meet the requested data rate R and QoS q. Optionally, the transmitter can include in the mapping the power level P for transmission on the K subchannels. Including a power level P is advantageous where the invention is implemented in a device that is limited by battery capacity, for example, a Mt phone, Personal Digital Assistant (PDA), or laptop computer.
  • At 406, the transmitter detects the energy or noise level on all of the available subchannels. According to the embodiment in FIG. 4, the OFDM system provides for N subchannels. The detected enemy level on each subchannel can be represented by the set D as follows:

  • D={D 1 , D 2 , . . . , D N}
  • Where D1 is the energy level detected on the first subchannel and D2 is the enemy level detected on the second subchannel, continuing on for all N subchannels.
  • At 407-414, the transmitter examines each value in set D to identify the subchannels whose noise level is below the required maximum noise level E. The transmitter begins the process at 407 by setting an index variable to the first value in set D. At 408, for the selected member of set D, the transmitter compares the energy level of the selected member with the threshold value E. If the subchannel has sufficiently low noise, it is added to set C at 409, If the noise is too high, the subchannel is dropped from consideration at 412. At 410, if set C has a sufficient number of subchannels to meet the requirement K established at 405, the transmitter can begin transmitting on the selected subchannels in set C at power P at 411, If the transmitter has not identified a sufficient number of subchannels meeting, the criteria, at 413 the transmitter advances to the next subchannel and continues to test each subchannel until a sufficient number of subchannels are identified, repeating steps 408-414.
  • In an alternative embodiment, the transmitter detects energy on subchannels individually until it has identified a sufficient number of subchannels to meet the requirements established at 405.
  • At 414, if the detected energy level for all of the subchannels have been tested and the transmitter has not identified a sufficient number of subchannels to meet the criteria K and E am optionally Pt established at 405, the transmitter can take any of the following actions:
      • At 445, the transmitter can select a new value qnew for the Quality of Service. qnew can be any value less than q.
      • At 404, the transmitter can select a new value rnew for the data rate. rnew can be any value less than r.
      • The transmitter could select both a lower QoS qnew at 415 and a lower data rate rnew at 404.
      • At 403, the transmitter can signal the application 401 that the requested R and q are not possible in the current network environment.
  • One example of a means for signaling the application that the requested transmission characteristics are unavailable is the Generic QoS API (GQoS) implemented in the Microsoft Windows protocol stack, which provides feedback to the application regarding the status of the network.
  • In response to a notification that the requested transmission characteristics are unavailable, the application 401 can respond in several different ways. For example, if the content to be transmitted is streaming video, the application 401 might choose to transmit lower quality or more highly compressed video and thus request a lower data rate for the transmission. If the content to be transmitted is VoIP communications and a minimal QoS cannot be obtained, the application 401 might cancel the attempt to make a connection and notify the user that the communication is not possible, or alternatively it could select a higher compression level for the encoded audio and request a lower data rate R at the same QoS from the transmitter. In another embodiment, the application 401 could prompt the user that a high quality connection is not possible but ask the user whether the application 401 should attempt to communicate at a lower quality. In the case where the application attempts to create a connection with different transmission properties, the transmitter will repeat steps 402-415 with the newly requested properties.
  • Another aspect of the invention is the possibility of minimizing the packet assembly delay for time sensitive low data rate streams such as VoIP traffic by attempting to minimize the number of OFDM subchannels allocated for transmission. In typical high data rate OFDM systems the OFDM symbol size exceeds the size of a VoIP packet. Commonly-implemented methods to address this issue are (1) the transmitter may send a nearly empty OFDM symbol or (2) the transmitter accumulates enough voice packets to transmit a full OFDM symbol before sending. In case (1), the overall efficiency of spectrum use is reduced while in case (2) audio quality is diminished due to the increased latency from the transmitter waiting for enough packets to accumulate to transmit a full symbol.
  • In order to better accommodate VoIP traffic, the mapping at 405 can attempt to minimize the number of subchannels to be used K. In this embodiment, the specific transmission requirements of Vow are satisfied without sacrificing high spectral efficiency. This embodiment could be implemented at the operating system level, where the operating system would request a certain data rate that is derived from the application along with the delay requirements. The subchannel mapping that occurs at 405-411 chooses the number of subchannels to match the requirements and channel conditions.
  • As illustrated in FIG. 5, in this embodiment, the operating system takes the following steps in response to a request from the application to optimize transmission characteristics to accommodate network traffic that requires low latency but does not require a full OF′DM symbol to transmit at the requested rate:
      • The application 501 requests a QoS q at 502, where that QoS includes low latency transmission (as for VoIP traffic) and a data rate R at 503,
      • At 505, the Operating System 504 computes the size of the symbol (number of bytes) based on the data rate and the maximum packetization delay for the data stream.
      • At 506, the Operating System computes the number of subchannels and the modulation scheme needed for transmitting the symbols given the channel conditions.
      • The Operating System continuously adjusts the modulation scheme and number of subchannels based on feedback from the transmitter 507,
  • Although VoIP is used as an illustrative example in this aspect of the invention, this aspect of the claimed invention can be applied in response to a request for transmission from any application that sends network packets smaller than a full OFDM symbol at the requested rate.
  • In yet another aspect of the invention the transmitter receives feedback from the receiver based on successful transmissions. This feedback could be, for example, in the form of acknowledgement packets. If no acknowledgement packets are received by the transmitter despite multiple retransmission attempts, the transmitter can conclude that the energy level given the modulation scheme is insufficient. In order to maintain the requested QoS, the transmitter can add subchannels dynamically to the set C of subchannels used for transmission. Another alternative approach in case the feedback indicates successful transmission is to lower the modulation scheme used. By selecting a lower order modulation scheme, the transmitter can achieve more robust transmission. Similarly, the lack of transmission errors over an extended period of time may be used to reduce the numbers of subchannels or increase the modulation to a higher order modulation scheme.
  • In another embodiment, the number of subchannels K is held constant but the transmitter selects the energy level based on the requested QoS, In this embodiment, high priority data streams are transmitted in a more robust way. For example, applications requesting QoS priority 7 under the IEEE 802.1Q standard typically transmit network control traffic, while priority 6 is used for VoIP traffic. Under IEEE 802.1Q, both priorities 6 and 7 require highly reliable transmission and low delay respectively. The transmitter selects robust transmission characteristics in response to the requested priorities, thus reducing the chance of packet errors and thus retransmissions. These characteristics could include a lower data rate or higher power transmission.
  • In another embodiment, an out-of-band channel is available for communication between the transmitter-receiver pair. For example, a dual band wireless access point may communicate with a dual band client. This communication could occur in the 802.11a (5 GHz) band. When the transmitter cannot identify a sufficient number of subchannels below the required energy threshold to achieve the requested QoS and data rate, the transmitter may select one of two solutions. The first solution is the preferred embodiment discussed above, wherein the transmitter signals to the application that the requested transmission characteristics are not possible, and the application may then alter the requested parameters as shown in FIG. 4. The second solution relies on the availability of reliable out-of-band signaling, as in a dual band wireless access point. In this embodiment, the application at the transmitter end of the connection can signal the application on the receiver end of the connection using the 0.4 GHz band at the lowest order modulation scheme. The signal sent from the transmitter to the receiver indicates that a requested QoS is not possible in the network environment. In this case, the receiver application may be able to accommodate a lower QoS, or the receiver may have a better signal-to-noise ratio than that detected by the transmitter. The receiver may then signal the transmitter to begin transmitting despite the energy levels detected by the transmitter.
  • FIG. 6 illustrates another embodiment of the invention, FIG. 6 shows a system 600 comprising an application 601, a subchannel/energy mapping module 602, a signaling module 603, and a noise detection module 604, The application 601 requests a data rate and QoS. The subchannel/energy mapping module 602 maps the requested data rate and QoS to a number of subchannels K and an energy threshold E. Independently, the noise detection module 604 detects the energy level on the available OFDM subchannels. The signaling module 603 processes the output of the noise detection module 604 and the subchannel/energy mapping module 602 to determine whether there are enough subchannels whose noise level is below the energy threshold E to meet the requirement of K subchannels. If the signaling module 603 determines that there are insufficient subchannels, it can either signal the subchannel/energy mapping module 602 to select different requirements, or it can signal the application 601 that the requested transmission characteristics are not available.
  • In another embodiment, the communication occurs over wires. The communication may occur over an Asymmetric Digital Subscriber Line (ADSL) system, over power lines, or over any other wired communication system implementing OFDM modulation.
  • In yet another embodiment, the invention relates to a computer-readable medium having computer-executable instructions for performing steps. The steps include receiving a requested data rate and Quality of Service from an application, mapping the requested transmission characteristics into a minimum number of subchannels, an energy threshold, and optionally the transmission power, identifying subchannels whose energy is below the required energy threshold, and signaling the application in the event that a sufficient number of subchannels cannot be identified.
  • Having thus described several aspects of at least one embodiment of this invention, it is to be appreciated various alterations, modifications, and improvements will readily occur to those skilled in the art. Such alterations, modifications, and improvements are intended to be part of this disclosure, and are intended to be within the spirit and scope of the invention. Accordingly, the foregoing description and drawings are by way of example only.

Claims (20)

What is claimed is:
1. A method performed on a computing device, the method comprising:
receiving, by the computing device, a serial digital data stream;
converting, by the computing device, the received serial digital data stream into a plurality of parallel digital data streams;
modulating, by the computing device, each of the plurality of parallel digital data streams onto a separate subchannel, where each separate subchannel is one of a plurality of subchannels of a channel, where the separate subchannels are selected based on a requested data transmission rate and on noise levels detected on various of the plurality of subchannels, the modulating resulting in modulated parallel digital data streams;
converting, by the computing device, the modulated parallel digital data streams into a modulated serial digital data stream;
converting, by the computing device, the modulated serial digital data stream into a modulated analog data stream that represents the received serial digital data stream; and
transmitting, by the computing device, the modulated analog data stream.
2. The method of claim 1 where each of the plurality of parallel digital data streams comprises frames of data divided from the received serial digital data stream.
3. The method of claim 1 where the modulating is based at least in part on a phase shift keying modulation scheme.
4. The method of claim 1 where the modulating is based at least in part on a quadrature amplitude modulation scheme.
5. The method of claim 1 further comprising selecting, based on a required data rate, a modulation scheme used in the modulating.
6. The method of claim 1 further comprising selecting, based on available subchannels, a modulation scheme used in the modulating.
7. The method of claim 1 further comprising adding, prior to the convertings, a cyclic prefix to each of the modulated parallel digital data streams.
8. A system comprising a computing device and at least one program module that are together configured for performing actions comprising:
receiving, by the computing device, a serial digital data stream;
converting, by the computing device, the received serial digital data stream into a plurality of parallel digital data streams;
modulating, by the computing device, each of the plurality of parallel digital data streams onto a separate subchannel, where each separate subchannel is one of a plurality of subchannels of a channel, where the separate subchannels are selected based on a requested data transmission rate and on noise levels detected on various of the plurality of subchannels, the modulating resulting in modulated parallel digital data streams;
converting, by the computing device, the modulated parallel digital data streams into a modulated serial digital data stream;
converting, by the computing device, the modulated serial digital data stream into a modulated analog data stream that represents the received serial digital data stream; and
transmitting, by the computing device, the modulated analog data stream.
9. The system of claim 8 where each of the plurality of parallel digital data streams comprises frames of data divided from the received serial digital data stream.
10. The system of claim 8 where the modulating is based at least in part on a phase shift keying modulation scheme.
11. The system of claim 8 where the modulating is based at least in part on a quadrature amplitude modulation scheme.
12. The system of claim 8 further comprising selecting, based on a required data rate, a modulation scheme used in the modulating.
13. The system of claim 8 further comprising selecting, based on available subchannels, a modulation used in the modulating.
14. The system of claim 8 further comprising adding, prior to the convertings, a cyclic prefix to each of the modulated parallel digital data streams.
15. At least one computer storage device having stored thereon computer-readable instructions that, when executed by a computing device, cause the computing device to perform actions comprising:
receiving, by the computing device, a serial digital data stream;
converting, by the computing device, the received serial digital data stream into a plurality of parallel digital data streams;
modulating, by the computing device, each of the plurality of parallel digital data streams onto a separate subchannel, where each separate subchannel is one of a plurality of subchannels of a channel, where the separate subchannels are selected based on a requested data transmission rate and on noise levels detected on various of the plurality of subchannels, the modulating resulting in modulated parallel digital data streams;
converting, by the computing device, the modulated parallel digital data streams into a modulated serial digital data stream;
converting, by the computing device, the modulated serial digital data stream into a modulated analog data stream that represents the received serial digital data stream; and
transmitting, by the computing device, the modulated analog data stream.
16. The at least one computer storage device of claim 15 where each of the plurality of parallel digital data streams comprises frames of data divided from the received serial digital data stream.
17. The at least one computer storage device of claim 15 here the modulating is based at least in part on a phase shift keying modulation scheme or on a quadrature amplitude modulation scheme.
18. The at least one computer storage device of claim 15 further comprising selecting, based on a required data rate, a modulation scheme used in the modulating.
19. The at least one computer storage device of claim 15 further comprising selecting, based on available subchannels, a modulation scheme used in the modulating.
20. The at least one computer storage device of claim 15 further comprising adding, prior to the convertings, a cyclic prefix to each of the modulated parallel digital data streams.
US14/562,470 2006-05-12 2014-12-05 Signaling to application lack of requested bandwidth Abandoned US20150180921A1 (en)

Priority Applications (3)

Application Number Priority Date Filing Date Title
US11/433,804 US8189621B2 (en) 2006-05-12 2006-05-12 Stack signaling to application with lack of requested bandwidth
US13/452,637 US8923340B2 (en) 2006-05-12 2012-04-20 Signaling to application lack of requested bandwidth
US14/562,470 US20150180921A1 (en) 2006-05-12 2014-12-05 Signaling to application lack of requested bandwidth

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US14/562,470 US20150180921A1 (en) 2006-05-12 2014-12-05 Signaling to application lack of requested bandwidth

Related Parent Applications (1)

Application Number Title Priority Date Filing Date
US13/452,637 Continuation US8923340B2 (en) 2006-05-12 2012-04-20 Signaling to application lack of requested bandwidth

Publications (1)

Publication Number Publication Date
US20150180921A1 true US20150180921A1 (en) 2015-06-25

Family

ID=38685060

Family Applications (7)

Application Number Title Priority Date Filing Date
US11/433,804 Expired - Fee Related US8189621B2 (en) 2006-05-12 2006-05-12 Stack signaling to application with lack of requested bandwidth
US13/449,312 Expired - Fee Related US8509265B2 (en) 2006-05-12 2012-04-18 Stack signaling to application with lack of requested bandwidth
US13/452,637 Expired - Fee Related US8923340B2 (en) 2006-05-12 2012-04-20 Signaling to application lack of requested bandwidth
US14/104,027 Active US9386055B2 (en) 2006-05-12 2013-12-12 Signaling to application lack of requested bandwidth
US14/562,470 Abandoned US20150180921A1 (en) 2006-05-12 2014-12-05 Signaling to application lack of requested bandwidth
US15/189,692 Abandoned US20160302102A1 (en) 2006-05-12 2016-06-22 Signaling to application lack of requested bandwidth
US15/189,603 Active US10182367B2 (en) 2006-05-12 2016-06-22 Signaling to application lack of requested bandwidth

Family Applications Before (4)

Application Number Title Priority Date Filing Date
US11/433,804 Expired - Fee Related US8189621B2 (en) 2006-05-12 2006-05-12 Stack signaling to application with lack of requested bandwidth
US13/449,312 Expired - Fee Related US8509265B2 (en) 2006-05-12 2012-04-18 Stack signaling to application with lack of requested bandwidth
US13/452,637 Expired - Fee Related US8923340B2 (en) 2006-05-12 2012-04-20 Signaling to application lack of requested bandwidth
US14/104,027 Active US9386055B2 (en) 2006-05-12 2013-12-12 Signaling to application lack of requested bandwidth

Family Applications After (2)

Application Number Title Priority Date Filing Date
US15/189,692 Abandoned US20160302102A1 (en) 2006-05-12 2016-06-22 Signaling to application lack of requested bandwidth
US15/189,603 Active US10182367B2 (en) 2006-05-12 2016-06-22 Signaling to application lack of requested bandwidth

Country Status (10)

Country Link
US (7) US8189621B2 (en)
EP (1) EP2018718A4 (en)
JP (1) JP5156004B2 (en)
KR (1) KR20090020565A (en)
CN (1) CN101444013B (en)
BR (1) BRPI0711403A2 (en)
MX (1) MX2008014240A (en)
RU (1) RU2441322C2 (en)
TW (1) TWI352534B (en)
WO (1) WO2007133779A1 (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20160302102A1 (en) * 2006-05-12 2016-10-13 Microsoft Technology Licensing, Llc Signaling to application lack of requested bandwidth
US9742529B2 (en) 2008-01-25 2017-08-22 Microsoft Technology Licensing, Llc Orthogonal frequency division multiple access with carrier sense
US9755879B2 (en) 2007-05-08 2017-09-05 Microsoft Technology Licensing, Llc OFDM transmission and reception for non-OFDM signals
US9774415B2 (en) 2006-12-12 2017-09-26 Microsoft Technology Licensing, Llc Cognitive multi-user OFDMA

Families Citing this family (30)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8009609B2 (en) * 2006-06-09 2011-08-30 Alcatel Lucent Maintaining quality of service for wireless communications
US20080165779A1 (en) * 2007-01-09 2008-07-10 Walter Weiss Methods, devices, and computer program products for forwarding packets using experimental bits to support service provider applications
US20080182574A1 (en) * 2007-01-25 2008-07-31 Telefonaktiebolaget L M Ericsson (Publ) Ultra-Wideband Mode Selection
US9270944B2 (en) * 2007-02-14 2016-02-23 Time Warner Cable Enterprises Llc Methods and apparatus for content delivery notification and management
US7929623B2 (en) * 2007-03-30 2011-04-19 Microsoft Corporation FEC in cognitive multi-user OFDMA
US8682336B2 (en) 2007-10-19 2014-03-25 Voxer Ip Llc Telecommunication and multimedia management method and apparatus
US8321581B2 (en) 2007-10-19 2012-11-27 Voxer Ip Llc Telecommunication and multimedia management method and apparatus
US8111713B2 (en) 2007-10-19 2012-02-07 Voxer Ip Llc Telecommunication and multimedia management method and apparatus
US8001261B2 (en) 2007-10-19 2011-08-16 Voxer Ip Llc Telecommunication and multimedia management method and apparatus
US8145780B2 (en) * 2007-10-19 2012-03-27 Voxer Ip Llc Telecommunication and multimedia management method and apparatus
US8380874B2 (en) 2007-10-19 2013-02-19 Voxer Ip Llc Telecommunication and multimedia management method and apparatus
US8391312B2 (en) 2007-10-19 2013-03-05 Voxer Ip Llc Telecommunication and multimedia management method and apparatus
US8706907B2 (en) 2007-10-19 2014-04-22 Voxer Ip Llc Telecommunication and multimedia management method and apparatus
US8699678B2 (en) 2007-10-19 2014-04-15 Voxer Ip Llc Telecommunication and multimedia management method and apparatus
US8180029B2 (en) 2007-06-28 2012-05-15 Voxer Ip Llc Telecommunication and multimedia management method and apparatus
US8090867B2 (en) 2007-10-19 2012-01-03 Voxer Ip Llc Telecommunication and multimedia management method and apparatus
US9071859B2 (en) 2007-09-26 2015-06-30 Time Warner Cable Enterprises Llc Methods and apparatus for user-based targeted content delivery
US8441968B2 (en) * 2008-07-08 2013-05-14 Marvell World Trade Ltd. Physical layer frame format design for wideband wireless communications systems
US8064396B2 (en) 2008-04-29 2011-11-22 Elektrobit Wireless Communications Oy Communication method and a radio system
KR101723389B1 (en) * 2011-01-10 2017-04-18 삼성전자주식회사 Method and apparatus for adaptive operation of application
US9225614B2 (en) 2011-11-17 2015-12-29 Google Inc. Service and application layer optimization using variable rate optical transmission
KR20130073360A (en) * 2011-12-23 2013-07-03 한국전자통신연구원 Data processing device of multi-carrier system and data processing method thereof
CN103716357B (en) * 2012-09-29 2017-06-20 中国移动通信集团广东有限公司 A mobile information synchronization method, and a mobile communication terminal apparatus
US20140201383A1 (en) * 2013-01-16 2014-07-17 Microsoft Corporation Distributed description over multiple links
TWI501574B (en) * 2013-05-06 2015-09-21 D Link Corp Power line network transmitter capable of switching noise detection and filtering
EP3028468A4 (en) * 2013-07-30 2017-08-30 Robert Bosch GmbH Adaptive methods for wireless camera communication
US9660800B2 (en) * 2013-11-06 2017-05-23 Navitas Solutions Fast data acquisition in digital communication
CN103946807B (en) 2013-11-20 2016-03-09 华为技术有限公司 A method of generating a snapshot, the system and apparatus
US9807713B2 (en) * 2014-11-14 2017-10-31 Telefonaktiebolaget Lm Ericsson (Publ) Synchronization in communications networks
GB2539977A (en) * 2015-06-30 2017-01-04 British Telecomm Communications Network

Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5852630A (en) * 1997-07-17 1998-12-22 Globespan Semiconductor, Inc. Method and apparatus for a RADSL transceiver warm start activation procedure with precoding
US20030236080A1 (en) * 2002-06-20 2003-12-25 Tamer Kadous Rate control for multi-channel communication systems
US20040110510A1 (en) * 2002-12-09 2004-06-10 Taehyun Jeon Apparatus and method for channel quality estimation and link adaptation in orthogonal frequency division multiplexing (OFDM) wireless communication system
US20050201295A1 (en) * 2004-03-12 2005-09-15 Jee-Hyun Kim Method and apparatus for transmitting/receiving channel quality information in a communication system using an orthogonal frequency division multiplexing scheme
US20060008014A1 (en) * 2004-07-07 2006-01-12 Satoshi Tamaki Method and adaptive modulation in multi-carrier communication
US20060128318A1 (en) * 2002-09-10 2006-06-15 Luigi Agarossi Transmission power optimization in ofdm wireless communication system
US20060274842A1 (en) * 2005-06-06 2006-12-07 Interdigital Technology Corporation Frequency domain joint detection for wireless communication systems
US7570953B2 (en) * 2004-01-12 2009-08-04 Intel Corporation Multicarrier communication system and methods for link adaptation using uniform bit loading and subcarrier puncturing
US7596127B1 (en) * 2001-10-31 2009-09-29 Vixs Systems, Inc. System for allocating data in a communications system and method thereof
US7933344B2 (en) * 2006-04-25 2011-04-26 Mircosoft Corporation OFDMA based on cognitive radio

Family Cites Families (242)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
BE635102A (en) 1962-07-19
US4210780A (en) 1978-03-27 1980-07-01 The Mitre Corporation Multiple access digital communications system
EP0577488B9 (en) * 1992-06-29 2007-10-03 Nippon Telegraph And Telephone Corporation Speech coding method and apparatus for the same
TW257779B (en) 1992-12-09 1995-09-21 Shell Internat Res Schappej Bv
FR2701178A1 (en) 1993-02-03 1994-08-05 Philips Electronique Lab Spread spectrum communication system with multiple users.
US5675572A (en) 1993-07-28 1997-10-07 Sony Corporation Orthogonal frequency division multiplex modulation apparatus and orthogonal frequency division multiplex demodulation apparatus
TW256789B (en) 1994-04-06 1995-09-11 China Textile Inst Process of producing flame retardant products by coating aqueous foam and hair implantation
FR2721461B1 (en) 1994-06-16 1996-09-06 France Telecom Signal formed of a plurality of orthogonal carrier frequencies organized to simplify receiving a source signal component, transmission method and corresponding receiver.
WO1996023371A1 (en) 1995-01-25 1996-08-01 Ntt Mobile Communications Network Inc. Mobile radio communication system
JP2601243B2 (en) 1995-07-12 1997-04-16 日本電気株式会社 Wireless communication system
US5790516A (en) 1995-07-14 1998-08-04 Telefonaktiebolaget Lm Ericsson Pulse shaping for data transmission in an orthogonal frequency division multiplexed system
US5729535A (en) 1995-12-29 1998-03-17 Lsi Logic Corporation Method and apparatus for adapting a computer for wireless communications
US5781543A (en) 1996-08-29 1998-07-14 Qualcomm Incorporated Power-efficient acquisition of a CDMA pilot signal
US6233456B1 (en) 1996-09-27 2001-05-15 Qualcomm Inc. Method and apparatus for adjacent coverage area handoff in communication systems
US6584144B2 (en) 1997-02-24 2003-06-24 At&T Wireless Services, Inc. Vertical adaptive antenna array for a discrete multitone spread spectrum communications system
US6175550B1 (en) 1997-04-01 2001-01-16 Lucent Technologies, Inc. Orthogonal frequency division multiplexing system with dynamically scalable operating parameters and method thereof
JPH1117643A (en) 1997-06-19 1999-01-22 Hitachi Denshi Ltd Ofdm modulator
US5867478A (en) 1997-06-20 1999-02-02 Motorola, Inc. Synchronous coherent orthogonal frequency division multiplexing system, method, software and device
US7773566B2 (en) 1998-06-01 2010-08-10 Tantivy Communications, Inc. System and method for maintaining timing of synchronization messages over a reverse link of a CDMA wireless communication system
JP3724940B2 (en) 1998-01-08 2005-12-07 株式会社東芝 Ofdm the diversity receiver
US7430257B1 (en) * 1998-02-12 2008-09-30 Lot 41 Acquisition Foundation, Llc Multicarrier sub-layer for direct sequence channel and multiple-access coding
DE19810695A1 (en) 1998-03-12 1999-09-16 Daimler Benz Aerospace Ag A method for detecting a pulsed useful signal
US6295272B1 (en) 1998-04-20 2001-09-25 Gadzoox Networks, Inc. Subchannel modulation scheme for carrying management and control data outside the regular data channel
DE69940235D1 (en) 1998-05-26 2009-02-26 Panasonic Corp Modulator, demodulator, and transmission system for transmitting OFDM-
JP3515690B2 (en) 1998-06-02 2004-04-05 松下電器産業株式会社 Ofdma signal transmission device and method
EP0964332B1 (en) 1998-06-10 2005-10-12 Sun Microsystems, Inc. Scheduling processes for resource allocation
US6041048A (en) 1998-06-12 2000-03-21 Motorola, Inc. Method for providing information packets from a packet switching network to a base site and corresponding communication system
US6609039B1 (en) 1998-07-27 2003-08-19 Neil Charles Schoen Simultaneous multi-user audio re-transmission digital radio module
US7079584B2 (en) 1998-08-10 2006-07-18 Kamilo Feher OFDM, CDMA, spread spectrum, TDMA, cross-correlated and filtered modulation
EP1050963B1 (en) 1998-11-12 2007-03-14 Matsushita Electric Industrial Co., Ltd. Receiver for digital terrestrial broadcasting
US7020071B2 (en) 1998-11-25 2006-03-28 Lucent Technologies Inc. Methods and apparatus for wireless communication using orthogonal frequency division multiplexing
US6760300B1 (en) 1999-02-17 2004-07-06 Imec High speed wireless OFDM transceiver modem
US20030015423A1 (en) 1999-03-04 2003-01-23 Lagreca Alfred J. Method and apparatus for calibrating a pH/ISE meter
EP1037484B1 (en) 1999-03-15 2009-01-14 Motorola, Inc. Time sharing of communications resources in cellular communications systems
US6466793B1 (en) 1999-05-28 2002-10-15 Ericsson Inc. Automatic frequency allocation (AFA) for wireless office systems sharing the spectrum with public systems
FI107770B (en) 1999-06-07 2001-09-28 Nokia Mobile Phones Ltd PDP contexts of the mobile management
US6763072B1 (en) 1999-08-25 2004-07-13 Victor Company Of Japan, Ltd. Method and apparatus for modulation and demodulation related to orthogonal frequency division multiplexing
US6456653B1 (en) * 1999-08-25 2002-09-24 Lucent Technologies Inc. Fast and accurate signal-to-noise ratio estimation technique for OFDM systems
US6633614B1 (en) 1999-09-15 2003-10-14 Telcordia Technologies, Inc. Multicarrier personal access communication system
US6327300B1 (en) 1999-10-25 2001-12-04 Motorola, Inc. Method and apparatus for dynamic spectrum allocation
US7324437B1 (en) 1999-11-27 2008-01-29 Deutsche Telekom Ag Method for co-channel interference cancellation in a multicarrier communication system
US6397368B1 (en) 1999-12-06 2002-05-28 Intellon Corporation Forward error correction with channel adaptation
JP3911378B2 (en) * 2000-02-16 2007-05-09 松下電器産業株式会社 Communication terminal apparatus and communication method
US6952454B1 (en) 2000-03-22 2005-10-04 Qualcomm, Incorporated Multiplexing of real time services and non-real time services for OFDM systems
JP3578966B2 (en) 2000-03-31 2004-10-20 日本電信電話株式会社 Multi-carrier modulation scheme for transmission circuit
US7028334B2 (en) * 2000-04-12 2006-04-11 Corente, Inc. Methods and systems for using names in virtual networks
KR100374338B1 (en) 2000-04-26 2003-03-03 삼성전자주식회사 Method of supporting power control on dcch in bs
US7020072B1 (en) 2000-05-09 2006-03-28 Lucent Technologies, Inc. Orthogonal frequency division multiplexing transmit diversity system for frequency-selective fading channels
US6987729B1 (en) 2000-05-11 2006-01-17 Lucent Technologies Inc. Method and apparatus for admission management in wireless communication systems
EP1283995B1 (en) 2000-05-26 2003-11-19 Roke Manor Research Limited Management module for software defined radio
US8363744B2 (en) 2001-06-10 2013-01-29 Aloft Media, Llc Method and system for robust, secure, and high-efficiency voice and packet transmission over ad-hoc, mesh, and MIMO communication networks
US6445773B1 (en) 2000-06-14 2002-09-03 Consultronics Limited DMT test method for determining ADSL capability of cables
US6721267B2 (en) 2000-08-01 2004-04-13 Motorola, Inc. Time and bandwidth scalable slot format for mobile data system
US6721569B1 (en) 2000-09-29 2004-04-13 Nortel Networks Limited Dynamic sub-carrier assignment in OFDM systems
AU9424201A (en) * 2000-10-13 2002-04-22 Genista Corp System, method, and apparatus for quality features for mobile and internet terminals
US7672381B1 (en) 2000-10-17 2010-03-02 Motorola, Inc. Method of multiple-carrier communication within a noncontiguous wideband spectrum and apparatus therefor
US6870808B1 (en) 2000-10-18 2005-03-22 Adaptix, Inc. Channel allocation in broadband orthogonal frequency-division multiple-access/space-division multiple-access networks
AU758813B2 (en) 2000-10-21 2003-04-03 Samsung Electronics Co., Ltd. Transmitting packet data in mobile communications systems
US20020086707A1 (en) 2000-11-15 2002-07-04 Struhsaker Paul F. Wireless communication system using block filtering and fast equalization-demodulation and method of operation
US6947748B2 (en) 2000-12-15 2005-09-20 Adaptix, Inc. OFDMA with adaptive subcarrier-cluster configuration and selective loading
JP4031707B2 (en) 2000-12-15 2008-01-09 アダプティックス インコーポレイテッド Multicarrier communication by group-based subcarrier allocation
US6961388B2 (en) 2001-02-01 2005-11-01 Qualcomm, Incorporated Coding scheme for a wireless communication system
JP3893881B2 (en) 2001-02-16 2007-03-14 株式会社日立製作所 Software radio and wireless system, certification system of software radio
US20020157058A1 (en) 2001-02-20 2002-10-24 Cute Ltd. System and method for feedback-based unequal error protection coding
US7158474B1 (en) 2001-02-21 2007-01-02 At&T Corp. Interference suppressing OFDM system for wireless communications
US6524610B2 (en) 2001-02-26 2003-02-25 Julia Muszynska Nutritional composition made from conventional foods for mixing onsite in a blender and treating patients with hepatic disorders
US6976202B1 (en) 2001-03-09 2005-12-13 Ikanos Communication Inc. Method and apparatus for time-frequency domain forward error correction for digital communication systems
US6934340B1 (en) * 2001-03-19 2005-08-23 Cisco Technology, Inc. Adaptive control system for interference rejections in a wireless communications system
JP2002290367A (en) * 2001-03-26 2002-10-04 Hitachi Kokusai Electric Inc Band division demodulation method and ofdm receiver
JP2002300181A (en) * 2001-03-30 2002-10-11 Nec Corp INTEGRATED NETWORK QoS CONTROL SYSTEM
US7035201B2 (en) 2001-04-20 2006-04-25 Mediatek Inc. Programmable transceiver structure of multi-rate OFDM-CDMA for wireless multimedia communications
US7206840B2 (en) 2001-05-11 2007-04-17 Koninklike Philips Electronics N.V. Dynamic frequency selection scheme for IEEE 802.11 WLANs
US7688899B2 (en) * 2001-05-17 2010-03-30 Qualcomm Incorporated Method and apparatus for processing data for transmission in a multi-channel communication system using selective channel inversion
US7072413B2 (en) 2001-05-17 2006-07-04 Qualcomm, Incorporated Method and apparatus for processing data for transmission in a multi-channel communication system using selective channel inversion
ES2188373B1 (en) 2001-05-25 2004-10-16 Diseño De Sistemas En Silencio, S.A. Procedure for optimizing communication system multiuser OFDM digital transmission over the electricity network.
EP1267513A3 (en) 2001-06-11 2006-07-26 Unique Broadband Systems, Inc. Multiplexing of multicarrier signals
US7542482B2 (en) 2001-08-16 2009-06-02 Qualcomm Incorporated Method and apparatus for message segmentation in a wireless communication system
US6990059B1 (en) 2001-09-05 2006-01-24 Cisco Technology, Inc. Interference mitigation in a wireless communication system
US7855948B2 (en) 2001-09-05 2010-12-21 Cisco Technology, Inc. Interference mitigation in a wireless communication system
US7151925B2 (en) 2001-09-10 2006-12-19 Industrial Technology Research Institute Software defined radio (SDR) architecture for wireless digital communication systems
US6869726B2 (en) * 2001-09-20 2005-03-22 Daramic, Inc. Reinforced multilayer separator for lead-acid batteries
US20030067961A1 (en) 2001-10-04 2003-04-10 Hudson John E. Wireless spread spectrum communications system, communications apparatus and method therefor
US7139320B1 (en) 2001-10-11 2006-11-21 Texas Instruments Incorporated Method and apparatus for multicarrier channel estimation and synchronization using pilot sequences
US7164649B2 (en) 2001-11-02 2007-01-16 Qualcomm, Incorporated Adaptive rate control for OFDM communication system
US7012883B2 (en) 2001-11-21 2006-03-14 Qualcomm Incorporated Rate selection for an OFDM system
US6771957B2 (en) 2001-11-30 2004-08-03 Interdigital Technology Corporation Cognition models for wireless communication systems and method and apparatus for optimal utilization of a radio channel based on cognition model data
US7391815B2 (en) 2001-12-06 2008-06-24 Pulse-Link, Inc. Systems and methods to recover bandwidth in a communication system
US8045935B2 (en) 2001-12-06 2011-10-25 Pulse-Link, Inc. High data rate transmitter and receiver
US7126984B2 (en) 2001-12-19 2006-10-24 Stmicroelectronics, Inc. Near-end crosstalk noise minimization and power reduction for digital subscriber loops
US7020110B2 (en) * 2002-01-08 2006-03-28 Qualcomm Incorporated Resource allocation for MIMO-OFDM communication systems
AU2003233409A1 (en) 2002-03-21 2003-10-08 Cognio, Inc. Ad-hoc control protocol governing use of an unlicensed or shared radio frequency band
SE524967C2 (en) 2002-04-18 2004-11-02 Terraplay Systems Ab Device for adaptive speed control in a packet switching network
KR100911138B1 (en) 2002-04-25 2009-08-06 삼성전자주식회사 Power controllable wireless mobile communication system of adaptive modulation and coding scheme and its method therefor
US7043681B2 (en) 2002-05-03 2006-05-09 Ibiquity Digital Corporation Digital audio broadcasting method and apparatus using complementary pattern-mapped convolutional codes
TW201101752A (en) 2002-05-10 2011-01-01 Interdigital Tech Corp Cognitive flow control based on channel quality conditions
US7260054B2 (en) 2002-05-30 2007-08-21 Denso Corporation SINR measurement method for OFDM communications systems
US20040005010A1 (en) 2002-07-05 2004-01-08 National University Of Singapore Channel estimator and equalizer for OFDM systems
EP1382614A1 (en) 2002-07-15 2004-01-21 Bayer HealthCare AG Process for the purification of interleukin-4 and its muteins
US7151755B2 (en) 2002-08-23 2006-12-19 Navini Networks, Inc. Method and system for multi-cell interference reduction in a wireless communication system
US7706405B2 (en) 2002-09-12 2010-04-27 Interdigital Technology Corporation System for efficient recovery of Node-B buffered data following MAC layer reset
KR100933155B1 (en) 2002-09-30 2009-12-21 삼성전자주식회사 Resource allocation apparatus and method of the virtual cell in a frequency division multiple access mobile communication system,
US7039004B2 (en) 2002-10-01 2006-05-02 Atheros Communications, Inc. Decision feedback channel estimation and pilot tracking for OFDM systems
ITTO20020858A1 (en) * 2002-10-04 2004-04-05 Rai Radiotelevisione Italiana The system for transmitting digital signals dvb / mpeg, particularly for satellite communications
US7317750B2 (en) 2002-10-31 2008-01-08 Lot 41 Acquisition Foundation, Llc Orthogonal superposition coding for direct-sequence communications
JP2004158965A (en) 2002-11-05 2004-06-03 Tokyo Electric Power Co Inc:The Centralized control method using protocol including centralized control
RU2298878C2 (en) 2002-11-07 2007-05-10 Нокиа Корпорейшн Transport-format data transfer
CN100446450C (en) 2002-11-07 2008-12-24 诺基亚公司 Transport format data transmission
JP4084639B2 (en) 2002-11-19 2008-04-30 株式会社エヌ・ティ・ティ・ドコモ Admission control method in a mobile communication, a mobile communication system, mobile station, admission controller and admission control program
JP4054253B2 (en) 2002-12-10 2008-02-27 京セラ株式会社 Communication system, a wireless communication terminal and the radio base station
US7920538B2 (en) 2003-12-08 2011-04-05 Investors Life Insurance Company Spectral reuse transceiver-based aggregation of disjoint, relatively narrow bandwidth (voice) channel segments of radio spectrum for wideband RF communication applications
US7756002B2 (en) 2003-01-30 2010-07-13 Texas Instruments Incorporated Time-frequency interleaved orthogonal frequency division multiplexing ultra wide band physical layer
JP2004266338A (en) * 2003-01-31 2004-09-24 Matsushita Electric Ind Co Ltd Multi-carrier transmission device, multi-carrier reception device and multi-carrier radio communication method
US20040203812A1 (en) 2003-02-18 2004-10-14 Malladi Durga Prasad Communication receiver with an adaptive equalizer that uses channel estimation
JP4250002B2 (en) 2003-03-05 2009-04-08 富士通株式会社 Adaptive modulation transmission system, and adaptive modulation control method
US8209680B1 (en) 2003-04-11 2012-06-26 Vmware, Inc. System and method for disk imaging on diverse computers
CA2427403C (en) 2003-04-21 2008-10-28 Regents Of The University Of Minnesota Space-time-frequency coded ofdm over frequency-selective fading channels
US7286603B2 (en) 2003-05-01 2007-10-23 Nokia Corporation Method and apparatus for increasing data rates in a wideband MC-CDMA telecommunication system
EP1480400A1 (en) 2003-05-21 2004-11-24 Siemens Mobile Communications S.p.A. A method of bit and power loading in OFDM communication systems with modulation and coding adaptation
US6934246B2 (en) 2003-06-16 2005-08-23 Motorola, Inc. System and method for reducing adjacent channel interference (ACI) in a multicarrier modulation system
US7103111B2 (en) 2003-06-16 2006-09-05 Motorola, Inc. System and method for generating a spectral efficient root raised cosine (RRC) pulse for increasing spectral efficiency
US7065150B2 (en) 2003-06-16 2006-06-20 Motorola, Inc. System and method for generating a root raised cosine orthogonal frequency division multiplexing (RRC OFDM) modulation
CA2530771C (en) 2003-06-27 2014-01-28 Nokia Corporation Method and apparatus for packet aggregation in a wireless communication network
EP1499081A3 (en) 2003-07-18 2007-01-03 Broadcom Corporation Multicarrier signal structure
US7448034B2 (en) 2003-07-30 2008-11-04 International Business Machines Corporation Build time determination and installation of drivers on cloned systems
KR100640461B1 (en) 2003-07-30 2006-10-30 삼성전자주식회사 Apparatus and method for assigning sub channel in a communication system using orthogonal frequency division multiple access scheme
CN1275480C (en) 2003-07-31 2006-09-13 上海贝尔阿尔卡特股份有限公司 Multi standard software radio (SDR) base band treating method
US7969857B2 (en) 2003-08-07 2011-06-28 Nortel Networks Limited OFDM system and method employing OFDM symbols with known or information-containing prefixes
US7394858B2 (en) 2003-08-08 2008-07-01 Intel Corporation Systems and methods for adaptive bit loading in a multiple antenna orthogonal frequency division multiplexed communication system
US7471932B2 (en) 2003-08-11 2008-12-30 Nortel Networks Limited System and method for embedding OFDM in CDMA systems
KR100965338B1 (en) * 2003-08-18 2010-06-22 엘지전자 주식회사 Sub-carriers allocating method for inter-cells interference reduction in ofdm cellular environments
KR100539925B1 (en) 2003-08-22 2005-12-28 삼성전자주식회사 Apparatus and method for sub-carrier alocation in ofdm system
JP2007503780A (en) 2003-08-27 2007-02-22 インターディジタル テクノロジー コーポレイションInterDigital Technology Corporation Assignment of subcarriers and bits for real-time services in multiuser orthogonal frequency division multiplexing (ofdm) system
JP2005086479A (en) 2003-09-09 2005-03-31 Hitachi Kokusai Electric Inc Transmission device
US20050085249A1 (en) 2003-10-16 2005-04-21 Pctel, Inc. Method, apparatus and system for pilotless frequency offset compensation in multipoint-to-point wireless systems with OFDM
JP4291673B2 (en) 2003-11-11 2009-07-08 株式会社エヌ・ティ・ティ・ドコモ Ofdm receiver
KR100557158B1 (en) 2003-11-12 2006-03-03 삼성전자주식회사 Apparatus for sub-carrier allocation in mimo ofdm mobile communication system and method thereof
KR100975720B1 (en) 2003-11-13 2010-08-12 삼성전자주식회사 Method and system for dynamic channel assignment and assignment of pilot channel in mimo-ofdm/ sdm system
US8406235B2 (en) * 2003-11-26 2013-03-26 Qualcomm Incorporated Quality of service scheduler for a wireless network
KR100557191B1 (en) 2003-12-01 2006-03-03 삼성전자주식회사 Soft modulation changing method for changing variably modulation way according to cell coverage range in broadband wireless access communication systems
JP2005167502A (en) 2003-12-01 2005-06-23 Ntt Docomo Inc Wireless communication system, control apparatus for transmission wireless station, control apparatus for reception wireless station, and subcarrier selecting method
KR20050053907A (en) 2003-12-03 2005-06-10 삼성전자주식회사 Method for assigning sub-carrier in a mobile communication system using orthogonal frequency division multiple access scheme
US7302009B2 (en) 2003-12-17 2007-11-27 Qualcomm Incorporated Broadcast transmission with spatial spreading in a multi-antenna communication system
US20050190800A1 (en) * 2003-12-17 2005-09-01 Intel Corporation Method and apparatus for estimating noise power per subcarrier in a multicarrier system
US6917598B1 (en) 2003-12-19 2005-07-12 Motorola, Inc. Unscheduled power save delivery method in a wireless local area network for real time communication
JP3910956B2 (en) 2003-12-26 2007-04-25 株式会社東芝 Channel estimator and receiving apparatus using the same for Ofdm wireless communication system
US20090323510A1 (en) 2004-01-06 2009-12-31 Simeon Furrer Modulation and demodulation of OFDM signals
US7194042B2 (en) 2004-01-13 2007-03-20 Qualcomm Incorporated Data transmission with spatial spreading in a mimo communication system
US7123580B2 (en) 2004-01-16 2006-10-17 Nokia Corporation Multiple user adaptive modulation scheme for MC-CDMA
US7430741B2 (en) 2004-01-20 2008-09-30 International Business Machines Corporation Application-aware system that dynamically partitions and allocates resources on demand
EP1560344B1 (en) 2004-01-28 2017-05-10 Harris Corporation Wireless ultra wideband network having frequency BIN transmission level setting and related methods
EP1876857A3 (en) 2004-02-27 2009-11-25 Research In Motion Limited Method and system for wireless channel selection by a mobile device
KR100810247B1 (en) 2004-03-05 2008-03-06 삼성전자주식회사 Method and apparatus for allocation of channel in a orthogonal frequency division multiple access system
JP4528541B2 (en) 2004-03-05 2010-08-18 株式会社東芝 Communication apparatus, communication method and a communication system,
KR100579192B1 (en) 2004-03-11 2006-05-11 삼성에스디아이 주식회사 Top-emission type organic electro luminescence display device and method for fabricating of the same
US7742533B2 (en) 2004-03-12 2010-06-22 Kabushiki Kaisha Toshiba OFDM signal transmission method and apparatus
US7827557B2 (en) 2004-03-24 2010-11-02 Hewlett-Packard Development Company, L.P. Method and apparatus for allocating resources to applications using a linearized objective function
US7417974B2 (en) 2004-04-14 2008-08-26 Broadcom Corporation Transmitting high rate data within a MIMO WLAN
KR101067772B1 (en) 2004-04-22 2011-09-28 엘지전자 주식회사 Method of Allocating Subcarriers for OFDM
US20050249127A1 (en) 2004-05-10 2005-11-10 Lucent Technologies, Inc. Method for subcarrier allocation
US7643811B2 (en) 2004-05-26 2010-01-05 Nokia Corporation Method and system for interference detection
JP4612474B2 (en) 2004-05-28 2011-01-12 パナソニック株式会社 Wireless communication device
WO2005122616A1 (en) 2004-06-10 2005-12-22 Matsushita Electric Industrial Co., Ltd. Communication terminal device, base station device, and radio communication system
US7296045B2 (en) 2004-06-10 2007-11-13 Hasan Sehitoglu Matrix-valued methods and apparatus for signal processing
CN101156322B (en) 2004-06-22 2013-11-20 苹果公司 Methods and systems for enabling feedback in wireless communication networks
US7289972B2 (en) 2004-06-25 2007-10-30 Virginia Tech Intellectual Properties, Inc. Cognitive radio engine based on genetic algorithms in a network
AT484142T (en) * 2004-07-05 2010-10-15 Ericsson Telefon Ab L M Apparatus and method for a push-initiated intelligence
JP4762619B2 (en) 2004-07-14 2011-08-31 パナソニック株式会社 Communication terminal device and wireless communication method
JP4181093B2 (en) 2004-07-16 2008-11-12 株式会社東芝 Wireless communication system
US7643583B1 (en) 2004-08-06 2010-01-05 Marvell International Ltd. High-precision signal detection for high-speed receiver
US8270512B2 (en) 2004-08-12 2012-09-18 Interdigital Technology Corporation Method and apparatus for subcarrier and antenna selection in MIMO-OFDM system
JP3786129B2 (en) 2004-08-20 2006-06-14 日本電気株式会社 Orthogonal frequency division multiplexing modem circuit
CA2578467A1 (en) 2004-08-25 2006-03-09 Padcom Holdings, Inc. Multi-network seamless roaming through a software-defined-radio
US7852746B2 (en) 2004-08-25 2010-12-14 Qualcomm Incorporated Transmission of signaling in an OFDM-based system
JP4447416B2 (en) * 2004-09-22 2010-04-07 株式会社エヌ・ティ・ティ・ドコモ Multi-band mobile communication system and a transmitter
KR100643280B1 (en) 2004-09-24 2006-11-10 삼성전자주식회사 Apparatus and method for managing sub channels dynamically
KR100754593B1 (en) 2004-10-11 2007-09-05 삼성전자주식회사 Apparatus and method for allocating sub-channel and power in a orthogonal frequency division multiplexing access system
US9161231B2 (en) 2004-10-14 2015-10-13 Alcatel Lucent Method and system for wireless networking using coordinated dynamic spectrum access
JP4698383B2 (en) 2004-10-26 2011-06-08 パナソニック株式会社 Wireless terminal device, management terminal device, and terminal management method
KR20060038131A (en) * 2004-10-29 2006-05-03 삼성전자주식회사 Method for uplink scheduling in a communication system using frequency hopping ??orthogonal frequency division multiple access scheme
CA2588781A1 (en) 2004-11-19 2006-05-26 The Trustees Of The Stevens Institute Of Technology Multi-access terminal with capability for simultaneous connectivity to multiple communication channels
JP2006191533A (en) 2004-12-09 2006-07-20 Matsushita Electric Ind Co Ltd Communication terminal equipment, control station, and multicarrier communication method
US8537760B2 (en) 2004-12-17 2013-09-17 Samsung Electronics Co., Ltd Method and system for dynamic hybrid multiple access in an OFDM-based wireless network
JP4681003B2 (en) 2004-12-21 2011-05-11 テレフオンアクチーボラゲット エル エム エリクソン(パブル) Transmitting apparatus and transmitting method for transmitting packet data unit in communication system
US8524822B2 (en) * 2005-01-11 2013-09-03 W. R. Grace & Co.—Conn. Vapor permeable liquid-applied membrane
SG124302A1 (en) 2005-01-13 2006-08-30 Oki Techno Ct Singapore Pte Architecture and protocol for software defined radio system
US7525988B2 (en) * 2005-01-17 2009-04-28 Broadcom Corporation Method and system for rate selection algorithm to maximize throughput in closed loop multiple input multiple output (MIMO) wireless local area network (WLAN) system
US7372890B2 (en) 2005-01-28 2008-05-13 Texas Instruments Incorporated Methods and systems for detecting and mitigating interference for a wireless device
US7769912B2 (en) 2005-02-17 2010-08-03 Samsung Electronics Co., Ltd. Multistandard SDR architecture using context-based operation reconfigurable instruction set processors
US7627048B2 (en) 2005-02-22 2009-12-01 Staccato Communications, Inc. Communication of interference mitigation related information between wireless devices
US8279985B2 (en) 2005-02-22 2012-10-02 Adaptix, Inc. Intelligent demodulation systems and methods in an OFDMA multicell network
JP4897783B2 (en) 2005-03-08 2012-03-14 クゥアルコム・インコーポレイテッドQualcomm Incorporated Transmission method and apparatus combining pulse position modulation and hierarchical modulation
US7742444B2 (en) * 2005-03-15 2010-06-22 Qualcomm Incorporated Multiple other sector information combining for power control in a wireless communication system
US20060211395A1 (en) 2005-03-15 2006-09-21 Intel Corporation Apparatus and method of detecting pilot carriers received on a fading channel
US7539463B2 (en) 2005-03-30 2009-05-26 Intel Corporation Techniques to enhance diversity for a wireless system
JP4541210B2 (en) 2005-03-31 2010-09-08 Kddi株式会社 Multi-carrier radio communication apparatus and subcarrier allocation method
KR20060106223A (en) 2005-04-06 2006-10-12 삼성전자주식회사 Apparatus and method for transmitting bit interleaved and coded modulation in an orthogonal frequency division multiplexing system
US7684473B2 (en) 2005-06-01 2010-03-23 Qualcomm Incorporated Receiver for wireless communication network with extended range
KR20060125087A (en) 2005-06-01 2006-12-06 삼성전자주식회사 Coding apparatus for orthogonal frequency division multiple access communication system and design method therof
JP4588548B2 (en) 2005-06-15 2010-12-01 株式会社エヌ・ティ・ティ・ドコモ Receiving apparatus and receiving method
US8463319B2 (en) 2005-06-17 2013-06-11 Honeywell International Inc. Wireless application installation, configuration and management tool
KR100713506B1 (en) 2005-07-05 2007-04-30 삼성전자주식회사 Method and apparatus for transmitting signal in a communication system
US7551641B2 (en) 2005-07-26 2009-06-23 Dell Products L.P. Systems and methods for distribution of wireless network access
US7548787B2 (en) 2005-08-03 2009-06-16 Kamilo Feher Medical diagnostic and communication system
US7260369B2 (en) 2005-08-03 2007-08-21 Kamilo Feher Location finder, tracker, communication and remote control system
WO2007022325A2 (en) * 2005-08-16 2007-02-22 Wionics Research Packet detection
CN1968492A (en) 2005-09-01 2007-05-23 三星电子株式会社 Method for allocating resouce in a mobile communication system
US7681239B2 (en) 2005-09-30 2010-03-16 Microsoft Corporation Modularly constructing a software defined radio
US7450559B2 (en) 2005-10-13 2008-11-11 Qualcomm Incorporated Method and apparatus for preserving compatibility between legacy mode(s) of operation and new mode(s) of operation in a communication system
KR20070041214A (en) 2005-10-14 2007-04-18 삼성전자주식회사 Method for uplink scheduling in a wireless mobile communication system
US7668262B2 (en) 2005-10-21 2010-02-23 Samsung Electro-Mechanics Systems, methods, and apparatuses for coarse spectrum-sensing modules
US8942161B2 (en) 2005-10-26 2015-01-27 Qualcomm Incorporated Weighted fair sharing of a wireless channel using resource utilization masks
CN101300768B (en) 2005-11-04 2011-02-23 艾利森电话股份有限公司 Method for self-adaptively coding, modulating and transmitting data word in radio communication system as well as transmission unit
KR101202901B1 (en) 2005-11-05 2012-11-19 삼성전자주식회사 Method for partitioning resource in a wireless communication system based on cognitive radio scheme
US7623599B2 (en) 2005-11-21 2009-11-24 Freescale Semiconductor, Inc. Blind bandwidth detection for a sample stream
EP1793520B1 (en) 2005-11-30 2012-02-29 Panasonic Corporation Configurable acknowledgement mode for a hybrid automatic repeat request protocol
CN104683085B (en) 2005-12-02 2018-12-07 Iii 控股6有限责任公司 The OFDM cognitive radio of the zero-overhead signaling of sub- carrier frequency with deletion
US7652979B2 (en) 2005-12-08 2010-01-26 University Of South Florida Cognitive ultrawideband-orthogonal frequency division multiplexing
TWI533721B (en) 2006-01-31 2016-05-11 Interdigital Tech Corp And a wireless communication system using a non-competitive base to provide a method and apparatus for channel
KR100735393B1 (en) 2006-02-15 2007-06-27 삼성전자주식회사 Connection method for multicast & broadcast service in broadband wireless access system
WO2007108077A1 (en) 2006-03-17 2007-09-27 Fujitsu Limited Base station device, mobile station device and sub-carrier allocating method
US7634016B2 (en) 2006-04-25 2009-12-15 Microsoft Corporation Variable OFDM subchannel coding and modulation
US8023574B2 (en) * 2006-05-05 2011-09-20 Intel Corporation Method and apparatus to support scalability in a multicarrier network
US8189621B2 (en) 2006-05-12 2012-05-29 Microsoft Corporation Stack signaling to application with lack of requested bandwidth
US9538388B2 (en) 2006-05-12 2017-01-03 Shared Spectrum Company Method and system for dynamic spectrum access
US20080002733A1 (en) 2006-06-30 2008-01-03 Ilan Sutskover Method and apparatus for scheduling transmissions in multiple access wireless networks
KR101145847B1 (en) 2006-07-14 2012-05-17 삼성전자주식회사 Signalling method of detecting hidden incumbent system in cognitive radio environment and channel fractioning method used to enable the method
US7813701B2 (en) 2006-08-29 2010-10-12 Piping Hot Networks Limited Interference optimized OFDM
US7869400B2 (en) 2006-10-16 2011-01-11 Stmicroelectronics, Inc. Method of inter-system coexistence and spectrum sharing for dynamic spectrum access networks-on-demand spectrum contention
US8520606B2 (en) 2006-10-23 2013-08-27 Samsung Electronics Co., Ltd Synchronous spectrum sharing based on OFDM/OFDMA signaling
US7920823B2 (en) 2006-12-08 2011-04-05 Microsoft Corporation System capability discovery for software defined radio
US8144793B2 (en) 2006-12-12 2012-03-27 Microsoft Corporation Cognitive multi-user OFDMA
US8072957B2 (en) 2007-01-18 2011-12-06 Proximetry, Inc. System and method for incorporating dynamic orthogonal frequency-division multiplexing into wireless network protocols
US7852745B2 (en) 2007-03-02 2010-12-14 Signalink Technologies Inc. Non-orthogonal frequency-division multiplexed communication through a non-linear transmission medium
US7929623B2 (en) 2007-03-30 2011-04-19 Microsoft Corporation FEC in cognitive multi-user OFDMA
US8289837B2 (en) 2007-05-04 2012-10-16 Qualcomm Incorporated Methods and apparatuses for multimode Bluetooth and WLAN operation concurrently
US7970085B2 (en) 2007-05-08 2011-06-28 Microsoft Corporation OFDM transmission and reception for non-OFDMA signals
US8166534B2 (en) 2007-05-18 2012-04-24 Microsoft Corporation Incorporating network connection security levels into firewall rules
US20090086706A1 (en) 2007-10-01 2009-04-02 The Hong Kong University Of Science And Technology Cross-layer multi-packet reception based medium access control and resource allocation
US8228850B2 (en) 2007-10-30 2012-07-24 Futurewei Technologies, Inc. Method and apparatus for transmitting control information in a system with new and legacy mobile stations
US8374130B2 (en) 2008-01-25 2013-02-12 Microsoft Corporation Orthogonal frequency division multiple access with carrier sense
US7800541B2 (en) 2008-03-31 2010-09-21 Golba Llc Methods and systems for determining the location of an electronic device
KR101098759B1 (en) 2008-04-21 2011-12-26 주식회사 코아로직 Universal blind mode detector, FFT-mode detector, guard-mode detector and memory sharing structure of the same universal blind mode detector and method of detecting universal blind mode

Patent Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5852630A (en) * 1997-07-17 1998-12-22 Globespan Semiconductor, Inc. Method and apparatus for a RADSL transceiver warm start activation procedure with precoding
US7596127B1 (en) * 2001-10-31 2009-09-29 Vixs Systems, Inc. System for allocating data in a communications system and method thereof
US20030236080A1 (en) * 2002-06-20 2003-12-25 Tamer Kadous Rate control for multi-channel communication systems
US20060128318A1 (en) * 2002-09-10 2006-06-15 Luigi Agarossi Transmission power optimization in ofdm wireless communication system
US20040110510A1 (en) * 2002-12-09 2004-06-10 Taehyun Jeon Apparatus and method for channel quality estimation and link adaptation in orthogonal frequency division multiplexing (OFDM) wireless communication system
US7570953B2 (en) * 2004-01-12 2009-08-04 Intel Corporation Multicarrier communication system and methods for link adaptation using uniform bit loading and subcarrier puncturing
US20050201295A1 (en) * 2004-03-12 2005-09-15 Jee-Hyun Kim Method and apparatus for transmitting/receiving channel quality information in a communication system using an orthogonal frequency division multiplexing scheme
US20060008014A1 (en) * 2004-07-07 2006-01-12 Satoshi Tamaki Method and adaptive modulation in multi-carrier communication
US20060274842A1 (en) * 2005-06-06 2006-12-07 Interdigital Technology Corporation Frequency domain joint detection for wireless communication systems
US7933344B2 (en) * 2006-04-25 2011-04-26 Mircosoft Corporation OFDMA based on cognitive radio

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20160302102A1 (en) * 2006-05-12 2016-10-13 Microsoft Technology Licensing, Llc Signaling to application lack of requested bandwidth
US10182367B2 (en) 2006-05-12 2019-01-15 Microsoft Technology Licensing Llc Signaling to application lack of requested bandwidth
US9774415B2 (en) 2006-12-12 2017-09-26 Microsoft Technology Licensing, Llc Cognitive multi-user OFDMA
US9866418B2 (en) 2006-12-12 2018-01-09 Microsoft Technology Licensing, Llc Cognitive multi-user OFDMA
US9755879B2 (en) 2007-05-08 2017-09-05 Microsoft Technology Licensing, Llc OFDM transmission and reception for non-OFDM signals
US10177953B2 (en) 2007-05-08 2019-01-08 Microsoft Technology Licensing, Llc OFDM transmission and reception for non-OFDM signals
US9742529B2 (en) 2008-01-25 2017-08-22 Microsoft Technology Licensing, Llc Orthogonal frequency division multiple access with carrier sense

Also Published As

Publication number Publication date
US20160309359A1 (en) 2016-10-20
TW200807991A (en) 2008-02-01
US8189621B2 (en) 2012-05-29
CN101444013A (en) 2009-05-27
US20160302102A1 (en) 2016-10-13
US10182367B2 (en) 2019-01-15
TWI352534B (en) 2011-11-11
WO2007133779A1 (en) 2007-11-22
US20120201317A1 (en) 2012-08-09
US9386055B2 (en) 2016-07-05
RU2441322C2 (en) 2012-01-27
MX2008014240A (en) 2008-11-14
KR20090020565A (en) 2009-02-26
US8509265B2 (en) 2013-08-13
BRPI0711403A2 (en) 2011-11-01
JP2009537097A (en) 2009-10-22
US8923340B2 (en) 2014-12-30
EP2018718A4 (en) 2013-04-10
US20070263653A1 (en) 2007-11-15
JP5156004B2 (en) 2013-03-06
US20120207233A1 (en) 2012-08-16
CN101444013B (en) 2013-07-10
EP2018718A1 (en) 2009-01-28
RU2008144587A (en) 2010-05-20
US20140098665A1 (en) 2014-04-10

Similar Documents

Publication Publication Date Title
US8553579B2 (en) Systems and methods for high rate OFDM communications
US6345071B1 (en) Fast retrain based on communication profiles for a digital modem
CN102523192B (en) Method and apparatus for transmitting uplink acknowledgement information in an OFDMA communication system
CN102835061B (en) Method and device for allocating and receiving tones for a frame
CN103796318B (en) On the data channel and control channel transmitting uplink control information
US7551937B2 (en) Method and device for allocating radio resources in wireless portable network system
US7440399B2 (en) Apparatus and method for efficient transmission of acknowledgments
US7933195B2 (en) Method and apparatus for transmitting/receiving channel quality information in a communication system using an orthogonal frequency division multiplexing scheme
US8565066B2 (en) System and method for an uplink acknowledgement transmission in carrier-aggregated wireless communication systems
CN101895502B (en) Apparatus and method for communicating using symbol modulated subcarriers
CN1278504C (en) Multi carrier transmission apparatus, multi carrier reception apparatus, and multi carrier radio communication method
CN1993956B (en) Channel estimation for a wireless communication system
US7974252B2 (en) Error control method, medium access control (MAC) frame designing method, and terminal registration method in wireless communication system, and recording medium
US6549512B2 (en) MDSL DMT architecture
KR100773131B1 (en) Method and apparatus for packet aggregation in a wireless communication network
US7292639B1 (en) Method and apparatus for peak to average power ratio reduction for orthogonal frequency division multiplex systems
US8095141B2 (en) Use of supplemental assignments
EP1943763B1 (en) System and method for improved data throughput in a wireless network
KR100561838B1 (en) Efficient transmission and receiving apparatus for multicast data and method thereof
CN1309180C (en) Method for multiple access and transmission in point-to-multipoint system on electrical network
EP2078402B1 (en) Joint use of multi-carrier and single-carrier multiplexing schemes for wireless communication
CN1665228B (en) Apparatus and method for allocating subchannels adaptively according to frequency reuse rates
JP3082756B2 (en) Multicarrier transmission system and method
US20050281226A1 (en) Apparatus and method for feedback of channel quality information in communication systems using an OFDM scheme
US20150163164A1 (en) Method and multi-carrier transceiver with stored application profiles for supporting multiple applications

Legal Events

Date Code Title Description
AS Assignment

Owner name: MICROSOFT TECHNOLOGY LICENSING, LLC, WASHINGTON

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:MICROSOFT CORPORATION;REEL/FRAME:034819/0001

Effective date: 20150123

AS Assignment

Owner name: MICROSOFT CORPORATION, WASHINGTON

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:HASSAN, AMER A.;KUEHNEL, THOMAS W.;WU, DEYUN;AND OTHERS;REEL/FRAME:035235/0630

Effective date: 20060509

STCB Information on status: application discontinuation

Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION