WO2003041283A2 - Procede et appareil pou la formation de faisceaux adaptatifs numeriques et la demodulation dans un recepteur a acces multiple a repartition d'espace/ acces multiple a repartition de code (sdma/cdma) - Google Patents
Procede et appareil pou la formation de faisceaux adaptatifs numeriques et la demodulation dans un recepteur a acces multiple a repartition d'espace/ acces multiple a repartition de code (sdma/cdma) Download PDFInfo
- Publication number
- WO2003041283A2 WO2003041283A2 PCT/US2002/035841 US0235841W WO03041283A2 WO 2003041283 A2 WO2003041283 A2 WO 2003041283A2 US 0235841 W US0235841 W US 0235841W WO 03041283 A2 WO03041283 A2 WO 03041283A2
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- present
- cinr
- demodulator
- polarization
- antenna
- Prior art date
Links
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B7/00—Radio transmission systems, i.e. using radiation field
- H04B7/02—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas
- H04B7/04—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas
- H04B7/08—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the receiving station
- H04B7/0837—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the receiving station using pre-detection combining
- H04B7/0842—Weighted combining
- H04B7/0848—Joint weighting
- H04B7/0857—Joint weighting using maximum ratio combining techniques, e.g. signal-to- interference ratio [SIR], received signal strenght indication [RSS]
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B7/00—Radio transmission systems, i.e. using radiation field
- H04B7/02—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas
- H04B7/10—Polarisation diversity; Directional diversity
Definitions
- the present application relates back to a provisional application, Serial
- the present invention relates to wireless communications systems. More particularly, the present invention relates to a novel and improved system, method, and apparatus to increase the capacity of transmitters/receivers that employ SDMA techniques and other methods of shaping antenna beams.
- SDMA or "smart antenna” techniques belong to the overall class of adaptive antenna array processing techniques. All adaptive antenna array techniques generally have the following features in common:
- An array of individual antenna elements is available to some receiver and/or transmitter.
- the system can independently adjust the amplitude and phase of the signal received from and/or transmitted by each element.
- An optimization process adjusts the amplitudes and phases of individual elements to optimize some objective function measured at the output of the receiver.
- RF adaptive beamforming (RFAB) systems provide multiple fixed amplitude and phase weights at the antenna terminals, usually in the form of some switched multiport matrix.
- Digital adaptive beamforming (DABF) systems perfo ⁇ n amplitude and phase weighting at baseband, so that each user essentially has its own uplink and/or downlink beam.
- DABF systems can be categorized in terms of: (1) the objective function employed to perform beamsteering; and (2) the optimization technique employed to optimize the objective function.
- a class of DABF systems that has gained widespread acceptance in the wireless industry is the class that relies on angle-of- arrival (AOA) estimates for individual signals and in turn uses this information to synthesize appropriate antenna weights.
- This class includes the popular Multiple Signal Classifier (MUSIC) algorithm (see R. O. Schmidt, “Multiple emitter location and signal parameter estimation,” IEEE Transactions on Antennas and Propagation, vol. AP-34, pp. 276-280); Root-MUSIC (A. Barabell, "Improving the resolution of eigenstructured based direction finding algorithms," Proc.
- MUSIC Multiple Signal Classifier
- CM A Constant modulus algorithms
- the second key feature of any DABF category is the optimization method employed to optimize the objective function.
- Most of the methods cited above employ what are known as signal-subspace or eigenstructure methods (see L. C. Godara, "Application of Antenna Arrays to Mobile Communications, Part II: Beam-Fonning and Direction-of-Arrival Considerations," Proceedings of the IEEE, vol. 85, no. 8, August 1997). These methods generally estimate and perform some sort of decomposition of the covariance matrix of receiver signal and noise measurements (e.g., W. S. Youn and C. K. Un, "Eigenstructure method for robust array processing," Electron. Lett., vol. 26, pp. 678-680, 1990; A. M. Haimovich and Y.
- the present invention builds on technology disclosed in a previous utility application filed on October 30, 2002 by G. Zancewicz, "System, Method, and Apparatus for Improving the Performance of Space Division Multiple Access and Other Systems that Shape Antenna Beams by Employing Postdetection Polarimetric Beamsteering and Utilizing Genetic Algorithms to Synthesize Beams," United States Utility Patent Application ("Polarimetric Utility Application”).
- the present invention builds on such technology by specifying: (1) an objective function based on actual CINR measurements at the output of a demodulator; and (2) an optimization method based on a genetic algorithm.
- the present invention obtains CINR measurements by estimating the desired signal energy and the undesired interference+noise energy at the output of, for example, a CDMA matched filter.
- the use of genetic algorithms in antenna array processors has been disclosed previously in G. Zancewicz, "Application for United States Letters Patent for Genetic Adaptive Antenna Array Processor," Attorney Docket 0T049.0020U1, August 1, 2000. OBJECT OF THE INVENTION
- the present invention seeks to expand incremental capacity exploiting specific characteristics of wireless signals, for example, CDMA or OFDM signals, in order to define optimally suitable adaptive uplink and/or downlink antenna beams.
- the present invention combines the processing for modulation/demodulation and digital adaptive beamforming in a single functional block.
- the DABF optimizes the antenna array element weights by using an objective function that measures the post-detection CINR output from the demodulator in the case of the uplink channel.
- the present invention combines processing for such beamforming with processing for CDMA modulation/demodulation or OFDM modulation/demodulation.
- the present invention employs genetic algorithms within the DABF process.
- the present invention matches the polarization of an antenna array with that of a mobile-of-interest by optimizing the polarization separately after optimizing antenna array weights.
- the rest of the present application describes the present invention in the case of a CDMA Demodulator on the uplink channel.
- the present invention clearly applies to all types of modulation and demodulation techniques, including without limitation: Amplitude Modulation (AM), Frequency Modulation (FM), and Quadrature Amplitude Modulation (QAM), as well as more complex modulation techniques such as CDMA (including without limitation: Direct Sequence Spread Spectrum (DSSS) and Frequency Hopping Spread Spectrum (FHSS)) and OFDM.
- DSSS Direct Sequence Spread Spectrum
- FHSS Frequency Hopping Spread Spectrum
- the specific functionality needed in the modulator/demodulator will depend on the specific modulation waveform and protocol employed. However, the present application clearly intends to apply the present invention to all such modulation/demodulation techniques.
- the present invention clearly applies to both demodulation on the uplink channel and modulation on the downlink channel.
- the present invention can apply to utilization of the system, apparatus, and methods on both a base station or user equipment.
- the present invention can apply to both mobile and fixed wireless networks.
- Figure 1 is a block diagram of an apparatus that is a genetic adaptive array (GAA) system
- Figure 2 is a flow chart of a method for matching the polarization of the GAA system
- Figure 3 is a diagram comparing a GAA system with a conventional system
- Figure 4 is a diagram showing a simulation model for a conventional system with angle of arrival (AOA) errors.
- Figure 5 is a Comparison of CINR of GAA v. CINR of Conventional System.
- the present invention includes the following system, apparatus, and method:
- ⁇ A system comprising an antenna array with complex weights that are adapted by a Genetic Algorithm (GA) Optimizer.
- the system utilizes the actual CINR from the output of the CDMA Demodulator as the GA fitness metric (figure of merit).
- GA Genetic Algorithm
- An apparatus combining the processing functionality of modulation/demodulation and digital adaptive beamforming in a single functional block.
- ⁇ A method of matching the polarization of an antenna array with that of the mobile-of-interest by: (1) optimizing the polarization separately after the GA optimizes the antenna array weights; or (2) optimizing the polarization jointly with the GA optimizing the weights.
- a GAA system comprises an antenna array with complex weights that are adapted by the GA Optimizer.
- the system utilizes the actual CINR from the output of the CDMA demodulator as the GA fitness metric (figure of merit).
- FIG. 1 shows a GAA system described by the present invention.
- the antenna array includes antenna elements 104 that transmit and/or receive signals to and or from the mobile-of-interest 100.
- the system separates the antenna elements 104 by a distance 106.
- the distances between the antenna elements can be constant or can vary.
- Table 3 in the Discussion section lists potential combinations of spacing or distances between antenna elements.
- a GA Optimizer 108 generates and adaptively adjusts a complex weight 110 for each i-th antenna element 104.
- a Component 112 sums the individual inputs from each antenna element
- a CDMA Demodulator 114 accepts a single complex- valued input sequence and demodulates the digital input sequence to produce a real-valued digital output sequence.
- the real-valued digital output produced by the CDMA Demodulator 114 corresponds to an estimate of some figure of merit of the digital input sequence, including without limitation: carrier-to-noise ratio (CNR), carrier-to-interference ratio (CIR), carrier-to-interference-and-noise ratio (CINR), bit error rate (BER), frame error rate (FER), packet error rate (PER), or energy- per-bit-to-noise (Eb No) ratio.
- the present invention utilizes the actual CINR as the figure of merit.
- the antenna arcay comprising antenna elements 104 receives input signals from the mobile-of-interest 100 and interfering mobiles 102.
- the antenna array transmits output to the Component 112.
- the Component 112 sums the individual signals from each antenna element 104 to produce a single complex-valued input sequence and transmits such sequence to the CDMA Demodulator 114.
- the CDMA Demodulator 114 demodulates the digital input sequence to produce a real-valued digital output sequence.
- the sequence corresponds to the actual CINR.
- the CDMA Demodulator 114 transmits the sequence to the GA Optimizer 108.
- the GA Optimizer 108 adaptively adjusts the complex array weights in order to maximize the CINR in accordance with the genetic algorithm implemented.
- the present application presents information on the set of simulation experiments that were performed to evaluate the performance of the GAA system.
- the GAA system comprises an antenna array that uses a genetic algorithm (GA) to adjust adaptively the complex weights of the array to maximize the CINR.
- GA genetic algorithm
- Prior utility applications by the present inventor cited in the "Background” section discuss the use of genetic algorithms in the present application.
- the simulation scenario includes a single mobile-of interest 100 with many multiple interfering mobiles 102 at random positions.
- the present invention used a different set of interferer positions for each experimental trial.
- the GA Optimizer 108 parameters relate to the internal structure of the GA and include parameters such as Number of Generations, Probability of
- the array topology relates to the spatial configuration of the array and includes parameters such as the number of elements and the element spacing.
- the polarization optimization comprised performing a "search" for the best polarization after the GA Optimizer 108 optimized the array weights.
- the present application compares the present invention to conventional systems by simulating estimation errors inherent in AOA estimation algorithms and comparing the performance to the GAA system.
- V out . . w n exp(-jk 0
- V 0 ut . ⁇ Pm , Parray> .
- the CINR is the ratio of the output due to the mobile-of-interest 100 to the output due to interfering mobiles 102 and the background noise floor:
- the simulation runs used random positions for the interfering mobiles 102.
- the simulation positioned the mobile-of-interest 100 at a range of 2000m and angle of 80 degrees.
- the simulation typically assumed the number of interfering mobiles 102 to be 100 and the number of trials (position configurations of all sources) to be 100.
- the GA Optimizer 108 is the engine that adaptively adjusts the complex array weights in order to maximize the CINR.
- the associated parameters include the following: ⁇ Number of generations ⁇ Number of chromosomes in population ⁇ Probability of crossover ⁇ Probability of mutation
- the present invention selects the values for the number of generations and number of chromosomes based on computational feasibility. In general, increasing the number of generations and number of chromosomes should result in better or equal performance. As the computational power of semiconductors improves, the present invention can increase the number of generations and number of chromosomes processed in the GA Optimizer 108.
- the array topology is related to the spatial configuration of the array and includes parameters such as the number of elements 104 and the element spacing 106.
- the present application considers many different topologies. The present application summarizes the results in the table below:
- the present application examines the performance gain from matching the polarization of the array to the mobile-of-interest.
- the present invention matches polarization by optimizing the polarization jointly with the GA optimizing the antenna array weights.
- the present invention matches polarization by optimizing the polarization separately with an "exhaustive" search after the GA optimizes the antenna array weights.
- the GA optimization loop runs over many iterations (generations) and converges to an optimal set of weights using circular polarization.
- the present invention considers the weights fixed and the polarization search then attempts to improve the CINR by trying different array polarization angles from the set ⁇ 0, 45, 90, 135, 180, -135, -90, -45 ⁇ .
- the present invention can include different sets of polarization angles, including without limitation: sets with different angles, sets with smaller or larger spaces between angles, and sets of angles that vary continuously, instead of discretely. Simulations show that the preferred embodiment yields higher performance.
- Figure 2 is a flow chart listing the steps in the method.
- the Antenna Array 200 generates an array output.
- the CDMA Demodulator 204 generates a real- valued digital output sequence.
- the real-valued digital output produced by the CDMA Demodulator 204 corresponds to an estimate of some figure of merit of the digital input sequence, including without limitation: carrier-to-noise ratio (CNR), carrier-to-interference ratio (CIR), carrier-to-interference-and-noise ratio (CINR), bit error rate (BER), frame error rate (FER), packet error rate (PER), or energy- per-bit-to-noise (Eb/No) ratio.
- this figure of merit is the actual CINR.
- the GA Optimizer 208 adaptively adjusts the complex array weights in order to maximize the CINR.
- the optimal set of weights is w opt 210.
- the GA optimization loop dete ⁇ nines whether the iteration is the last one generated in accordance with any criteria set by the GA Optimizer 208. If no 214, the method returns to Step 202 until it converges to an optimal set of weights. If yes 216, the method considers the antenna array weights fixed and then proceeds to conduct a search for the optimal polarization.
- the Polarization Optimizer searches for the optimal polarization by trying different array polarization angles from any set of polarization angles.
- the set of polarization angles can include ⁇ 0, 45, 90, 135, 180, -135, -90, -45 ⁇ .
- the Polarization Optimizer determines the optimal polarization and then adaptively adjusts the polarization vectors for each i-th antenna element.
- the present application makes several assumptions in order to characterize the conventional system.
- the main assumption is that any conventional system will utilize some type of AOA (angle of arrival) algorithm that estimates the source directions and feeds this information into the DABF (digital adaptive beam former) optimization algorithm to update the complex weights of the array.
- AOA angle of arrival
- DABF digital adaptive beam former
- the present application presents simulations that suggest that the CINR is very sensitive to AOA errors, especially as the number of interfering mobiles increases.
- the GAA system instead looks directly at the output of the CDMA demodulator and feeds the CINR into the GA optimizer that adapts the complex array weights.
- Figure 3 compares these two systems.
- the present application implements MUSIC.
- the present application implements the Cramer-Rao bound in the interest of applying the simulation to a general model.
- the Cramer-Rao bound represents the lower bound for any maximum-likelihood estimate and therefore applies regardless of the specific AOA estimation algorithm used.
- the present application applies random angle errors to the position vectors of the mobile-of-interest and interferer mobiles.
- the present application sets the variance of the angle errors to be the Cramer-Rao bound variance. Therefore, this noise is inherent in any conventional system that uses AOA estimation information for the purposes of array weight optimization.
- the present application uses noisy positions (positions with random errors added) as inputs to the Optimizer that determine the optimal weights. Once the Optimizer determines the weights, the CINR is evaluated at the true positions. This mismatch effectively simulates the performance degradation due to AOA estimation errors.
- Figure 4 shows the simulation model.
- the present application compares the conventional system with AOA errors and the preferred embodiment of the present invention by evaluating the performance as the Number of Interferers and the variance of the angle error in position varies.
- the present application summarizes the simulation results in the following table and graph.
- Table 4 Comparison of CINR of GAA with CINR of Conventional System
- the preferred embodiment of the present invention generates significantly higher CINR than a conventional system.
- the preferred embodiment improves its relative performance as the number of mobile interferers increases.
- the preferred embodiment improves its relative performance as the AOA errors increase.
- wireless networks that operate in environments with many reflecting surfaces, e.g., wireless local area networks in indoor environments, the potential for AOA errors can increase.
- the preferred embodiment could generate particularly higher performance than a conventional system could in such networks.
- the utility application describes the present invention in detail with particular reference to preferred embodiments, sequence of steps, and number of steps, other embodiments, step sequences, and a larger or smaller number of steps can achieve the same results. Variations and modifications of the present invention will be obvious to those skilled in the art. The inventor intends to cover in the claims of the present application all such variations, modifications, and equivalents.
Landscapes
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Radio Transmission System (AREA)
- Variable-Direction Aerials And Aerial Arrays (AREA)
Abstract
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
AU2002340424A AU2002340424A1 (en) | 2001-11-07 | 2002-11-07 | Digital adaptive beamforming and demodulation apparatus and method |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US33702801P | 2001-11-07 | 2001-11-07 | |
US60/337,028 | 2001-11-07 |
Publications (2)
Publication Number | Publication Date |
---|---|
WO2003041283A2 true WO2003041283A2 (fr) | 2003-05-15 |
WO2003041283A3 WO2003041283A3 (fr) | 2003-11-06 |
Family
ID=23318785
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/US2002/035841 WO2003041283A2 (fr) | 2001-11-07 | 2002-11-07 | Procede et appareil pou la formation de faisceaux adaptatifs numeriques et la demodulation dans un recepteur a acces multiple a repartition d'espace/ acces multiple a repartition de code (sdma/cdma) |
Country Status (2)
Country | Link |
---|---|
AU (1) | AU2002340424A1 (fr) |
WO (1) | WO2003041283A2 (fr) |
Cited By (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2005062497A1 (fr) * | 2003-12-22 | 2005-07-07 | Telefonaktiebolaget Lm Ericsson (Publ) | Procede de mesure d'ordonnancement spatial |
CN103916355A (zh) * | 2014-03-28 | 2014-07-09 | 西安电子科技大学 | 一种认知ofdm网络中子载波的分配方法 |
US9184498B2 (en) | 2013-03-15 | 2015-11-10 | Gigoptix, Inc. | Extending beamforming capability of a coupled voltage controlled oscillator (VCO) array during local oscillator (LO) signal generation through fine control of a tunable frequency of a tank circuit of a VCO thereof |
US9275690B2 (en) | 2012-05-30 | 2016-03-01 | Tahoe Rf Semiconductor, Inc. | Power management in an electronic system through reducing energy usage of a battery and/or controlling an output power of an amplifier thereof |
US9509351B2 (en) | 2012-07-27 | 2016-11-29 | Tahoe Rf Semiconductor, Inc. | Simultaneous accommodation of a low power signal and an interfering signal in a radio frequency (RF) receiver |
US9531070B2 (en) | 2013-03-15 | 2016-12-27 | Christopher T. Schiller | Extending beamforming capability of a coupled voltage controlled oscillator (VCO) array during local oscillator (LO) signal generation through accommodating differential coupling between VCOs thereof |
US9666942B2 (en) | 2013-03-15 | 2017-05-30 | Gigpeak, Inc. | Adaptive transmit array for beam-steering |
US9716315B2 (en) | 2013-03-15 | 2017-07-25 | Gigpeak, Inc. | Automatic high-resolution adaptive beam-steering |
US9722310B2 (en) | 2013-03-15 | 2017-08-01 | Gigpeak, Inc. | Extending beamforming capability of a coupled voltage controlled oscillator (VCO) array during local oscillator (LO) signal generation through frequency multiplication |
US9780449B2 (en) | 2013-03-15 | 2017-10-03 | Integrated Device Technology, Inc. | Phase shift based improved reference input frequency signal injection into a coupled voltage controlled oscillator (VCO) array during local oscillator (LO) signal generation to reduce a phase-steering requirement during beamforming |
US9837714B2 (en) | 2013-03-15 | 2017-12-05 | Integrated Device Technology, Inc. | Extending beamforming capability of a coupled voltage controlled oscillator (VCO) array during local oscillator (LO) signal generation through a circular configuration thereof |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4720712A (en) * | 1985-08-12 | 1988-01-19 | Raytheon Company | Adaptive beam forming apparatus |
US5274844A (en) * | 1992-05-11 | 1993-12-28 | Motorola, Inc. | Beam pattern equalization method for an adaptive array |
US6301470B1 (en) * | 1998-06-05 | 2001-10-09 | Siemens Aktiengesellschaft | Radio communications receiver and method of recovering data from radio signals |
-
2002
- 2002-11-07 WO PCT/US2002/035841 patent/WO2003041283A2/fr not_active Application Discontinuation
- 2002-11-07 AU AU2002340424A patent/AU2002340424A1/en not_active Abandoned
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4720712A (en) * | 1985-08-12 | 1988-01-19 | Raytheon Company | Adaptive beam forming apparatus |
US5274844A (en) * | 1992-05-11 | 1993-12-28 | Motorola, Inc. | Beam pattern equalization method for an adaptive array |
US6301470B1 (en) * | 1998-06-05 | 2001-10-09 | Siemens Aktiengesellschaft | Radio communications receiver and method of recovering data from radio signals |
Cited By (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
AU2003290488B2 (en) * | 2003-12-22 | 2009-04-09 | Telefonaktiebolaget Lm Ericsson (Publ) | A measurement method for spatial scheduling |
CN1886914B (zh) * | 2003-12-22 | 2012-12-12 | 艾利森电话股份有限公司 | 用于空间调度的测量方法 |
WO2005062497A1 (fr) * | 2003-12-22 | 2005-07-07 | Telefonaktiebolaget Lm Ericsson (Publ) | Procede de mesure d'ordonnancement spatial |
US9275690B2 (en) | 2012-05-30 | 2016-03-01 | Tahoe Rf Semiconductor, Inc. | Power management in an electronic system through reducing energy usage of a battery and/or controlling an output power of an amplifier thereof |
US9509351B2 (en) | 2012-07-27 | 2016-11-29 | Tahoe Rf Semiconductor, Inc. | Simultaneous accommodation of a low power signal and an interfering signal in a radio frequency (RF) receiver |
US9716315B2 (en) | 2013-03-15 | 2017-07-25 | Gigpeak, Inc. | Automatic high-resolution adaptive beam-steering |
US9184498B2 (en) | 2013-03-15 | 2015-11-10 | Gigoptix, Inc. | Extending beamforming capability of a coupled voltage controlled oscillator (VCO) array during local oscillator (LO) signal generation through fine control of a tunable frequency of a tank circuit of a VCO thereof |
US9531070B2 (en) | 2013-03-15 | 2016-12-27 | Christopher T. Schiller | Extending beamforming capability of a coupled voltage controlled oscillator (VCO) array during local oscillator (LO) signal generation through accommodating differential coupling between VCOs thereof |
US9666942B2 (en) | 2013-03-15 | 2017-05-30 | Gigpeak, Inc. | Adaptive transmit array for beam-steering |
US9722310B2 (en) | 2013-03-15 | 2017-08-01 | Gigpeak, Inc. | Extending beamforming capability of a coupled voltage controlled oscillator (VCO) array during local oscillator (LO) signal generation through frequency multiplication |
US9780449B2 (en) | 2013-03-15 | 2017-10-03 | Integrated Device Technology, Inc. | Phase shift based improved reference input frequency signal injection into a coupled voltage controlled oscillator (VCO) array during local oscillator (LO) signal generation to reduce a phase-steering requirement during beamforming |
US9837714B2 (en) | 2013-03-15 | 2017-12-05 | Integrated Device Technology, Inc. | Extending beamforming capability of a coupled voltage controlled oscillator (VCO) array during local oscillator (LO) signal generation through a circular configuration thereof |
CN103916355A (zh) * | 2014-03-28 | 2014-07-09 | 西安电子科技大学 | 一种认知ofdm网络中子载波的分配方法 |
Also Published As
Publication number | Publication date |
---|---|
AU2002340424A1 (en) | 2003-05-19 |
WO2003041283A3 (fr) | 2003-11-06 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US6677898B2 (en) | Method for controlling array antenna equipped with single radiating element and a plurality of parasitic elements | |
US7248897B2 (en) | Method of optimizing radiation pattern of smart antenna | |
CN108650200B (zh) | 高低频混合组网系统的低频辅助信道估计方法 | |
Nwalozie et al. | A simple comparative evaluation of adaptive beam forming algorithms | |
JP2002368663A (ja) | 適応アンテナ装置 | |
Basha et al. | A constructive smart antenna beam-forming technique with spatial diversity | |
JP2007159130A (ja) | 分散型アンテナ移動通信システムにおける上り受信方法及び装置 | |
CN110138422A (zh) | 基于稀疏编码和无相位解码的毫米波通信快速波束对准方法 | |
WO2003041283A2 (fr) | Procede et appareil pou la formation de faisceaux adaptatifs numeriques et la demodulation dans un recepteur a acces multiple a repartition d'espace/ acces multiple a repartition de code (sdma/cdma) | |
CN100442904C (zh) | 用于群播业务系统的下行波束赋形方法 | |
Khan et al. | Antenna beam-forming for a 60 Ghz transceiver system | |
Nawaz et al. | Auxiliary beam pair enabled initial access in mmwave systems: Analysis and design insights | |
Liu et al. | A dynamic subarray structure in reconfigurable intelligent surfaces for terahertz communication systems | |
Bo | Realization and simulation of DOA estimation using MUSIC algorithm with uniform circular arrays | |
EP1680870A1 (fr) | Procedes et des appareils sans fil pour traiter des signaux comprenant l'estimation des directions d'arrivee | |
CN117060954A (zh) | 一种基于mimo通信与感知技术的通感一体化波束设计方法 | |
CN116722896A (zh) | 超方向性天线阵列多用户预编码方法、设备及介质 | |
Al-Ardi et al. | Performance evaluation of the LMS adaptive beamforming algorithm used in smart antenna systems | |
Wang et al. | Fast Millimeter-Wave Base Station Discovery via Data-driven Beam Training Optimization | |
Khormuji et al. | Statistical beam codebook design for mmWave massive MIMO systems | |
Xiao et al. | AoA Estimation with Practical Antenna Arrays Using Neural Networks | |
SHIRVANI et al. | A new switched-beam setup for adaptive antenna array beamforming | |
US11469804B1 (en) | Sectorized analog beam search system | |
Mostafa et al. | Closed‐Loop Transmit Diversity Techniques for Small Wireless Terminals and Their Performance Assessment in a Flat Fading Channel | |
JP3740063B2 (ja) | 基地局装置およびダイバーシチ制御方法 |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AK | Designated states |
Kind code of ref document: A2 Designated state(s): AE AG AL AM AT AU AZ BA BB BG BR BY BZ CA CH CN CO CR CU CZ DE DK DM DZ EC EE ES FI GB GD GE GH GM HR HU ID IL IN IS JP KE KG KP KR KZ LC LK LR LS LT LU LV MA MD MG MK MN MW MX MZ NO NZ OM PH PL PT RO RU SD SE SG SI SK SL TJ TM TN TR TT TZ UA UG US UZ VN YU ZA ZM ZW |
|
AL | Designated countries for regional patents |
Kind code of ref document: A2 Designated state(s): GH GM KE LS MW MZ SD SL SZ TZ UG ZM ZW AM AZ BY KG KZ MD RU TJ TM AT BE BG CH CY CZ DE DK EE ES FI FR GB GR IE IT LU MC NL PT SE SK TR BF BJ CF CG CI CM GA GN GQ GW ML MR NE SN TD TG |
|
121 | Ep: the epo has been informed by wipo that ep was designated in this application | ||
DFPE | Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101) | ||
122 | Ep: pct application non-entry in european phase | ||
NENP | Non-entry into the national phase in: |
Ref country code: JP |
|
WWW | Wipo information: withdrawn in national office |
Country of ref document: JP |