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
  • H04B7/0413—MIMO systems
• • 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
  • H04B7/0491—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas using two or more sectors, i.e. sector diversity
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01Q—ANTENNAS, i.e. RADIO AERIALS
  • H01Q3/00—Arrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system
  • H01Q3/24—Arrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system varying the orientation by switching energy from one active radiating element to another, e.g. for beam switching
• • 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
  • H04B7/0413—MIMO systems
  • H04B7/0456—Selection of precoding matrices or codebooks, e.g. using matrices antenna weighting
  • H04B7/046—Selection of precoding matrices or codebooks, e.g. using matrices antenna weighting taking physical layer constraints into account
• • 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
  • H04B7/06—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station
  • H04B7/0697—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station using spatial multiplexing
• • 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
  • H04B7/0802—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 antenna selection
  • H04B7/0805—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 antenna selection with single receiver and antenna switching
  • H04B7/0814—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 antenna selection with single receiver and antenna switching based on current reception conditions, e.g. switching to different antenna when signal level is below threshold
• • 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
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04W—WIRELESS COMMUNICATION NETWORKS
  • H04W72/00—Local resource management
  • H04W72/04—Wireless resource allocation
  • H04W72/044—Wireless resource allocation based on the type of the allocated resource
  • H04W72/046—Wireless resource allocation based on the type of the allocated resource the resource being in the space domain, e.g. beams

Definitions

• the present invention relates to the transmission and reception of signals in a wireless, multi-antenna MIMO (Multiple Input Multiple Output) transmission system.
• the invention can be applied in a number of fields, such as in the field of high-bitrate home multimedia networks.
• MIMO technology The technology used most frequently in this equipment to transmit signals is MIMO technology. This technology is known to increase transmission capacities by multiplying signal transmission paths and improve the robustness of transmission using spatial multiplexing and spatio-temporal coding techniques.
• MIMO technology involves transmitting and receiving signals using a plurality of transmission channels with different characteristics to obtain separate signals and therefore increase the probability of at least one signal not being affected by fading.
• Signals are received or transmitted via a plurality of radio channels associated with a plurality of antennas.
• MIMO technology becomes less efficient in environments dominated by interference. And yet, with the constantly increasing amount of wireless equipment in homes, it has become essential to improve this technique for the transmission of signals in domestic environments.
• FIG. 1 An MIMO beamforming technique, illustrated in figure 1 , has therefore been developed for MIMO transmission in noisy environments.
• this solution uses a plurality of omnidirectional antennas connected to the inputs/outputs of the MIMO chip. These antennas are controlled together to obtain a radiation pattern with maximal values in the desired propagation directions and minimal values in the unwanted propagation directions. According to this technique, the form of the radiation pattern is obtained through signal processing in the MIMO chip.
• any jammers and interferences picked up by the equipment's omnidirectional antennas are always present on radio channels and lead to saturation, dynamic linearity and noise problems, which deteriorate the receiver's sensitivity,
• the radiation pattern that can be achieved depends greatly on the number of antennas (or radiation elements), the geometric availability of antennas in relation to each other and the performances of each antenna in relation to each other; indeed, a relatively high minimal number of antennas is generally required to obtain the desired radiation pattern form; but, increasing the number of antennas, of which there can be up to 8 in the standard Wifi 1 1 n case, means increasing the number of radio transmission and reception channels in the MIMO chip, which increases the cost and consumption of the equipment,
• the geometry of the network of antennas and the type of antenna are determined in the circuit integration phase and are often dependent on the form and size of the printed circuit card and the space remaining on this card for the antennas, which means that certain geometries are not possible.
• One purpose of the invention is to provide a multi-antenna device capable of transmitting and receiving MIMO signals to overcome some or all of the aforementioned disadvantages.
• a purpose of the invention is to provide a multi- antenna device capable of transmitting and receiving MIMO signals that is efficient in terms of speed and robust in environments dominated by interferences, and which transmits the least possible electromagnetic radiation into the environment in which it is placed.
• the invention proposes to use the cluster propagation phenomenon illustrated in figure 2.
• This figure represents the angles of departure and angles of arrival, in terms of a MIMO device's antennas, in signals being propagated inside a building. These angles are presented in the horizontal plane (plane H) and vertical plane (plane V) of the antenna.
• signal energy is essentially propagated in a reduced number of directions known as prioritized directions. This means that, from the receiver side, the radiations arriving at the antennas with significant energy are found in a limited number of angular sectors in plane H and plane V and, when the transmission paths of these radiations are followed to the transmitter, these radiations also correspond to radiations transmitted in a limited number of angular sectors in plane H and plane V.
• plane H is cut into angular sectors of around 60° as illustrated h figure 3, this shows, in this propagation example, that the significant radiations received by the receiver are present in the angular sectors [0° ,60°], [-180,°-120°] and [-60° , 0°].
• These radiations are transmitted in the transmitter in angular sectors [0° ,60°], [120° , 180°] and [-180° , -120°] of plane H (Horizontja For all of these sectors, in transmission and reception, the opening in plane V (Vertical) is around 60° and corresponds to the sector [-30° , 30°] of plane V
• the radiations transmitted in other angular sectors do not reach, or only very partially reach, the receiver. The energy of these sectors is therefore wasted and unnecessarily contributes to increasing background noise and interferences.
• the invention is therefore intended for a signal transmission and/or reception device in a MIMO system consisting of:
• N being greater than or equal to 2;
• the antenna system consists of at least one so-called multi-sector antenna, with M angular sectors in a horizontal plane capable of selectively receiving and/or transmitting said N signals in one or more of said M angular sectors, said M angular sectors not overlapping each other and together forming a global angular sector of 360 degrees, where
• the device also consists of switching means, mounted between the MIMO module and the antenna system to connect each of the N inputs/outputs of the MIMO module with P angular sectors of the at least one multi-sector antenna, where 1 ⁇ P ⁇ M, according to a switching diagram determined using control means in accordance with a criteria representing the quality of the reception of signals by said device or another device.
• the device in transmission, does not transmit signals in every direction, but only in the predefined prioritized directions, which reduces the quantity of electromagnetic waves transmitted and concentrates the energy transmitted in the prioritized directions.
• the device In reception, the device only receives the signals from these prioritized directions, which reduces the cost of signal processing as well as the energy consumption of the device.
• the antenna system consists of N multi-sector antennas with M angular sectors and the switching means consisting of N switching circuits, each input/output of the MIMO module being connected to one of said N multi-sector antennas via one of said N switching circuits.
• Each of said N multi-sector antennas includes Q inputs/outputs, Q being less than or equal to 2 M -1 , each of said Q inputs/outputs being connected to a specific combination of angular sectors of the multi-sector antenna.
• each multi-sector antenna no more than D angular sectors are connected via a switching circuit to an input/output of the MIMO module, where D ⁇ M.
• the number D corresponds to the maximum number of prioritized directions accepted by the device. For example, it can be considered that the device will use a maximum of 3 prioritized directions. D can therefore be fixed . In this case, it is not necessary for the antennas
• the antenna system consists of a multi-sector antenna with M angular sectors, where M>N, and the switching means consist of a switching circuit, said multi-sector antenna consisting of
• the number M of angular sectors of the multi-sector antennas is preferably equal to 6 as it has been discovered that, statistically, the angular opening of a cluster in plane H is typically 60° . 6 sectors are therefore typically required to cover the entire space (360°). Moreover, each sector has an angular opening in the vertical plane of 60° . In certain situations, it may be worth increasing the number of sectors, but 6 sectors represents a good compromise in terms of complexity-performance and cost-performance.
• the M angular sectors of said at least one multi-sector antenna present identical openings in a vertical plane.
• the M angular sectors each present an opening of at least 120° between the -60° and +60° angles in the vertical plane.
• they each present an opening of at least 60° between the -30° and +30° agles in the vertical plane.
• Figure 1 represents the diagram of a MIMO signal transmission device implementing a beamforming technique
• FIG. 2 shows, in diagram form, the angle of departure and the angle of arrival in plane H and plane V of the signals transmitted and received in a domestic environment
• Figure 3 represents the diagrams of figure 2 in which prioritized signal propagation directions have been identified
• Figure 4 represents a diagram of a first embodiment for a device according to the invention
• Figure 5 represents a diagram of a second embodiment for a device according to the invention
• the invention device includes:
• MIMO module 10 consisting of N inputs/outputs ES-
• an antenna system 30 consisting of N multi-sector antennas 30-i . . . 30N for transmitting or receiving N signals, each antenna consisting of M angular sectors, and
• switching means 20 mounted between the antenna system and the MIMO module and consisting of N switching circuits 20I ...20N-
• Each input/output ES, of the MIMO module is connected to inputs/outputs of the antenna 30, via the switching circuit 20,, with i e .
• the inputs/outputs of the antenna 30,, which are connected to the output ES, of the MIMO module, are selected using a switching diagram implemented by the switching circuit 20,. This diagram is determined using control means 40 according to a signal reception quality criterion.
• Each antenna 30, includes, in plane H, M angular sectors sensitively not overlapping each other and together forming a global angular sector of 360 degrees.
• Each antenna 30, is capable of selectively transmitting or receiving signals in P angular sectors, where 1 ⁇ P ⁇ M.
• Each angular sector or combination of angular sectors corresponds to a specific radiation diagram.
• the P angular sectors through which the MIMO signal associated with the input ES, is transmitted or received are selected using the switching circuit 20i according to a switching diagram determined using control means.
• the switching circuit 20, is used to connect the ES, input/output with the input/output of antenna 30,, which is connected to the selected P angular sectors.
• the switching diagram used by the switching circuit 20, is determined using control means 40.
• These control means 40 may be included in the MIMO module 10. This is determined using an algorithm based on MIMO signal reception quality used by the device if concerned with a transmission/reception device or by the MIMO signal reception device if the present device is only a MIMO signal transmission device.
• the signal reception quality can be defined using one or more values provided by the MIMO value, particularly the RSSI (Received Signal Strength Indication) value, the SINR (Signal to Interference plus Noise Ratio) value, the BER (Bit Error Rate) and the PER (Packet Error Rate).
• the number of prioritized signal propagation directions in plane H is generally reduced.
• this number of prioritized directions is equal to 3 in plane H.
• D the maximum number of prioritized directions permitted. It is considered, for example, that D will be less than or equal to 3 or 4.
• the number of inputs/outputs of antenna 30, can then be reduced to , each input/output being connected to up to D angular sectors, and the number of switching diagrams that switching circuit 20, must
• the invention device can be simplified to further reduce its cost, as illustrated in figure 5.
• the device consists of just one multi- sector antenna 130, with M angular sectors where M>N, which is connected to an MIMO module 1 10 via a single switching circuit 120.
• the MIMO module 1 10 consists of N inputs/outputs ES, and antenna 130 includes M inputs/outputs each connected to a specific angular sector from the M angular sectors.
• the switching circuit 120 connects the N inputs/outputs ES, with N inputs/outputs of antenna 130 according to a switching circuit selected using control means 140.
• each of the N MIMO signals is received or transmitted via its own angular sector from the M angular sectors of antenna 130.
• the angular sectors selected by the control methods 140 each correspond to a prioritized signal propagation direction.
• the 2 MIMO signals are each transmitted or received in its own angular sector corresponding to a prioritized signal propagation direction.
• the control means 140 must then have at least two prioritized directions determined.
• the width of the angular sectors is about 60° in the horizontal plane and between -30° and +30° in the v ertical plane (or elevation plane).
• device B transmits learning symbols through each of the possible configurations (or combinations) of N sectors from M angular sectors; device A listens for the learning symbols transmitted by device B and determines, for each configuration of N sectors from M transmission sectors (device B) and each configuration of N sectors from N reception sectors (device A), a quality indicator (RSSI or SINR or BER or PER); in total,
• the configuration showing the highest quality indicator is selected for device A in order to communicate with device B;
• device A transmits learning signals with the configuration selected during the first step; device B listens for the learning symbols transmitted by device A and determines a quality indicator (RSSI or SINR or BER or PER) for each possible configuration of N sectors from M
• RSSI quality indicator
• SINR SINR
• BER BER
• N! ( M _ N ) ! quality indicators are then determined and the configuration showing the highest quality indicator is selected for device B in order to communicate with device A. It should be noted that the SINR indicator appears to be the most suitable indicator in an environment dominated by interferences.
• the second step or both steps can be repeated periodically in order to take into account changes in the propagation environment.
• it may be decided to maintain the configurations of devices A and B while the transmission channel varies slightly, in other words so that the quality indicator does not fall below a predefined limit.
• the invention device is capable of functioning with a classic device consisting of a conventional omnidirectional antenna, a portable device, for example. If A indicates the invention device and B indicates the classic device, the learning phase takes place as follows. Device A listens for the learning symbols transmitted by device B through its omnidirectional antenna and determines, for each configuration (or combination) of N sectors from M sectors, a quality criterion (RSSI or SINR).
• RSSI quality criterion
• j y indicators are thus determined and the configuration with the highest quality indicator is selected for device A in order to communicate with device B.
• the invention device Compared with the existing MIMO devices consisting of omnidirectional antennas and using the beamforming technique, the invention device provides the following advantages:
• the interference rate is reduced in the front radio channel (directive antennas) and reduces the risk of saturation or disturbance of the radio channels of the MIMO module,
• the invention device consists of N multi-sector antennas and N switching circuits (corresponding to figures 4 and 6), signal transmission is also improved.
• the expected gain is equal to around GTx+GRx, where GTx corresponds to the gain in transmission and GRx corresponds to the gain in reception.
• the expected gain is lower, in the order of GTx+GRx-10 logN, N being the number of MIMO chains, but the structure of the device is less complex.

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• Engineering & Computer Science (AREA)
• Computer Networks & Wireless Communication (AREA)
• Signal Processing (AREA)
• Radio Transmission System (AREA)
• Mobile Radio Communication Systems (AREA)

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• 2012
  • 2012-06-07 FR FR1255300A patent/FR2991837A1/fr not_active Withdrawn
• 2013
  • 2013-05-31 CN CN201380029816.0A patent/CN104380719A/zh active Pending
  • 2013-05-31 JP JP2015515487A patent/JP2015520587A/ja not_active Withdrawn
  • 2013-05-31 EP EP13727124.3A patent/EP2859723B1/en active Active
  • 2013-05-31 US US14/405,592 patent/US20150155921A1/en not_active Abandoned
  • 2013-05-31 KR KR20147034203A patent/KR20150020550A/ko not_active Withdrawn
  • 2013-05-31 WO PCT/EP2013/061318 patent/WO2013182496A1/en not_active Ceased
  • 2013-06-06 TW TW102120019A patent/TW201351909A/zh unknown

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