Apparatus, system and method of handover of a beamformed link

Some demonstrative embodiments include devices, systems and/or methods of handover of a wireless beamformed link. For example, an apparatus may include a wireless communication unit to communicate between a wireless communication node and a mobile device via a beamformed link between the wireless communication node and the mobile device, the wireless communication unit is to determine a handover candidate for handing over the mobile device, based on at least one beamforming parameter of the beamformed link.

TECHNICAL FIELD

Embodiments described herein generally relate to handover of a beamformed link formed by an antenna array.

BACKGROUND

Some wireless communication systems may communicate over the Millimeter wave (mmWave) frequency band, e.g., the 60 GHz Frequency band. A mmWave propagation has a few major distinctive features in comparison with lower frequency bands, e.g., the frequency bands of 2.4-5 GHz. For example, the mmWave propagation may have a propagation loss greater than the propagation loss in the lower frequency bands, and may have Quasi-optical propagation properties.

A mmWave communication system may use high-gain directional antennas to compensate for large path loss and/or employ beam-steering techniques. Design of appropriate antenna system and/or further signal processing may be an important aspect of mmWave communication system development.

Multi-element phased antenna arrays may be used, for example, for creation of a directional antenna pattern. A phased antenna array may form a directive antenna pattern or a beam, which may be steered by setting appropriate signal phases at the antenna elements.

A handover process may be utilized for handing-over a session between a base station and a mobile device. The handover may often be time-consuming, e.g., due to necessity in performing signal quality measurement and/or making a decision for handing over the mobile device. The delays for such handovers may reduce the throughput performance and/or may delay the handover procedure.

DETAILED DESCRIPTION

Some embodiments may be used in conjunction with devices and/or networks operating in accordance with existing Wireless-Gigabit-Alliance (WGA) specifications (Wireless Gigabit Alliance, Inc WiGig MAC and PHY Specification Version1.1, April2011, Final specification) and/or future versions and/or derivatives thereof, devices and/or networks operating in accordance with existing IEEE 802.11 standards (IEEE802.11-2012, IEEE Standard for Information technology—Telecommunications and information exchange between systems Local and metropolitan area networks—Specific requirements Part11: Wireless LAN Medium Access Control(MAC)and Physical Layer(PHY)Specifications, Mar.29, 2012; IEEE802.11task group ac(TGac) (“IEEE802.11-09/0308r12—TGac Channel Model Addendum Document”);IEEE802.11task group ad(TGad) (IEEE P802.11ad Standard for Information Technology—Telecommunications and Information Exchange Between Systems—Local and Metropolitan Area Networks—Specific Requirements—Part11: Wireless LAN Medium Access Control(MAC)and Physical Layer(PHY)Specifications—Amendment3: Enhancements for Very High Throughput in the60GHz Band)) and/or future versions and/or derivatives thereof, devices and/or networks operating in accordance with existing WirelessHD™ specifications and/or future versions and/or derivatives thereof, units and/or devices which are part of the above networks, and the like.

The term “communicating” as used herein with respect to a wireless communication signal includes transmitting the wireless communication signal and/or receiving the wireless communication signal. For example, a wireless communication unit, which is capable of communicating a wireless communication signal, may include a wireless transmitter to transmit the wireless communication signal to at least one other wireless communication unit, and/or a wireless communication receiver to receive the wireless communication signal from at least one other wireless communication unit.

Some demonstrative embodiments may be used in conjunction with a WLAN. Other embodiments may be used in conjunction with any other suitable wireless communication network, for example, a wireless area network, a “piconet”, a WPAN, a WVAN and the like.

Some demonstrative embodiments may be used in conjunction with a Heterogeneous Network (HetNet), which may utilize a deployment of a mix of technologies, frequencies, cell sizes and/or network architectures, e.g., including cellular, mmWave, and/or the like. In one example, the HetNet may include a radio access network having layers of different-sized cells ranging from large macrocells to small cells, for example, picocells and femtocells.

Other embodiments may be used in conjunction with any other suitable wireless communication network.

Some demonstrative embodiments may be used in conjunction with a wireless communication network communicating over a frequency band of 60 GHz. However, other embodiments may be implemented utilizing any other suitable wireless communication frequency bands, for example, an Extremely High Frequency (EHF) band (the millimeter wave (mmwave) frequency band), e.g., a frequency band within the frequency band of between 20 Ghz and 300 GHZ, a WLAN frequency band, a WPAN frequency band, a frequency band according to the WGA specification, and the like.

The phrase “peer to peer (PTP or P2P) communication”, as used herein, may relate to device-to-device communication over a wireless link (“peer-to-peer link”) between a pair of devices. The P2P communication may include, for example, wireless communication over a direct link within a QoS basic service set (BSS), a tunneled direct-link setup (TDLS) link, a STA-to-STA communication in an independent basic service set (IBSS), or the like.

The phrase “mmWave frequency band” as used herein may relate to a frequency band above 20 GHz, e.g., a frequency band between 20 GHz and 300 GHz.

The phrases “directional multi-gigabit (DMG)” and “directional band” (DBand), as used herein, may relate to a frequency band wherein the Channel starting frequency is above 40 GHz.

The phrases “DMG STA” and “mmWave STA (mSTA)” may relate to a STA having a radio transmitter, which is operating on a channel that is within the mmWave or DMG band.

The term “beamforming”, as used herein, may relate to a spatial filtering mechanism, which may be used at a transmitter and/or a receiver to improve one or more attributes, e.g., the received signal power or signal-to-noise ratio (SNR) at an intended receiver.

The term “cell”, as used herein, may include a combination of network resources, for example, downlink and optionally uplink resources. The resources may be controlled and/or allocated, for example, by a wireless communication node (also referred to as a “node” or a “base station”), or the like. The linking between a carrier frequency of the downlink resources and a carrier frequency of the uplink resources may be indicated in system information transmitted on the downlink resources.

Reference is now made toFIG. 1, which schematically illustrates a block diagram of a system100, in accordance with some demonstrative embodiments.

As shown inFIG. 1, in some demonstrative embodiments, system100may include one or more wireless communication devices capable of communicating content, data, information and/or signals via a wireless medium (WM). For example, system100may include one or more wireless communication nodes, e.g., including nodes101and150, and one or more mobile devices, e.g., including mobile device140. The wireless medium may include, for example, a radio channel, a cellular channel, an RF channel, a Wireless Fidelity (WiFi) channel, an IR channel, and the like. One or more elements of system100may optionally be capable of communicating over any suitable wired communication links.

In some demonstrative embodiments, one or more elements of system100may perform the functionality of a Heterogeneous Network (HetNet), which may utilize a deployment of a mix of technologies, frequencies, cell sizes and/or network architectures, for example, including cellular, mmWave, and/or the like, e.g., as described below.

In one example, the HetNet may be configured to provide a service through a first wireless communication environment, e.g., WLAN, and to maintain the service when switching to another communication environment, e.g., a cellular network. The HetNet architecture may enable utilizing a mixture of wireless communication environments, e.g., a mmWave environment and a cellular environment, for example, to optimally respond to rapid changes in customer demand, reduce power consumption, reduce cost, increase efficiency and/or achieve any other benefit.

In some demonstrative embodiments, node101, node150and mobile device140may form and/or communicate as part of one or more wireless communication networks. For example, node101and mobile device140may form and/or may communicate as part of a wireless communication cell, e.g., as described below.

In some demonstrative embodiments, nodes101and/or150may include or may perform the functionality of a Base Station (BS), an Access Point (AP), a WiFi node, a Wimax node, a cellular node, e.g., an Evolved Node B (eNB), a station, a hot spot, a network controller, and the like.

In some demonstrative embodiments, mobile device140may include, for example, a User Equipment (UE), a mobile computer, a laptop computer, a notebook computer, a tablet computer, an Ultrabook™ computer, a mobile internet device, a handheld computer, a handheld device, a storage device, a PDA device, a handheld PDA device, an on-board device, an off-board device, a hybrid device (e.g., combining cellular phone functionalities with PDA device functionalities), a consumer device, a vehicular device, a non-vehicular device, a portable device, a mobile phone, a cellular telephone, a PCS device, a mobile or portable GPS device, a DVB device, a relatively small computing device, a non-desktop computer, a “Carry Small Live Large” (CSLL) device, an Ultra Mobile Device (UMD), an Ultra Mobile PC (UMPC), a Mobile Internet Device (MID), an “Origami” device or computing device, a video device, an audio device, an A/V device, a gaming device, a media player, a Smartphone, or the like.

In some demonstrative embodiments, node101, node150and/or mobile device140may include one or more wireless communication units to perform wireless communication between node101, node150and/or mobile device140and/or with one or more other wireless communication devices, e.g., as described below. For example, node101may include a wireless communication unit110, node150may include a wireless communication unit152and/or mobile device140may include a wireless communication unit142.

In some demonstrative embodiments, wireless communication units110,152and142may include, or may be associated with, one or more antennas. In one example, wireless communication unit110may be associated with at least one antenna array108; wireless communicate unit152may be associated with one or more antennas154; and/or wireless communication unit142may be associated with one or more antennas144.

Antennas108,154and/or144may include any type of antennas suitable for transmitting and/or receiving wireless communication signals, blocks, frames, transmission streams, packets, messages and/or data. For example, antennas108,154and/or144may include any suitable configuration, structure and/or arrangement of one or more antenna elements, components, units, assemblies and/or arrays. Antennas108,154and/or144may include, for example, antennas suitable for directional communication, e.g., using beamforming techniques. For example, antennas108,154and/or144may include a phased array antenna, a multiple element antenna, a set of switched beam antennas, and/or the like. In some embodiments, antennas108,154and/or144may implement transmit and receive functionalities using separate transmit and receive antenna elements. In some embodiments, antennas108,154and/or144may implement transmit and receive functionalities using common and/or integrated transmit/receive elements.

In some demonstrative embodiments, nodes101and/or150and/or mobile device140may also include, for example, one or more of a processor120, a memory unit122, and a storage unit124. Nodes101and/or150and/or mobile device140may optionally include other suitable hardware components and/or software components. In some demonstrative embodiments, some or all of the components of node101may be enclosed in a common housing or packaging, and may be interconnected or operably associated using one or more wired or wireless links. In other embodiments, components of node101may be distributed among multiple or separate devices.

In some demonstrative embodiments, antenna array108may include a plurality of antenna elements, e.g., as described below. The plurality of antenna elements of the antenna array may be configured, for example, for creation of a highly-directional antenna patterns. The plurality of antenna elements may include, for example, about 16-36 antenna elements, or any other number of antenna elements, which may be placed in a predefined geometry. The plurality of antenna elements may be configured to form one or more highly directive antenna patterns or beams, which may be steered by setting appropriate signal phases at the antenna elements, e.g., as described below.

In some demonstrative embodiments, wireless communication unit110may be configured to control antenna array108to generate and steer the plurality of beams to be directed to a plurality of other devices, e.g., including node150and mobile device140. Wireless communication unit110may communicate with the plurality of other devices via a plurality of wireless communication links over the plurality of beams formed by antenna array108, as described in detail below.

In some demonstrative embodiments, one or more elements of system100may utilize the mmWave communication band to provide wireless connectivity for a relatively large coverage area. In one example, elements of system100may be deployed, for example, in outdoor spaces, e.g., a street, a stadium, and the like, and/or large indoor areas, e.g., conference halls, and the like.

For example, system100may include a plurality of small cells, e.g., a large number of small cells, which may be deployed to cover the large coverage area, e.g., as described below with reference toFIG. 3. A cell may include a wireless communication node, e.g., a BS, which may be configured to cover and/or serve a relatively small number of users, for example, mobile devices, e.g., User Equipment (UE), and the like. The deployment of the small cells may provide, for example, high-speed wireless access for communication by many users, e.g., simultaneously.

In one example, a first cell may include node101, which may serve one or more users, e.g., including mobile device140; and a second cell may include node150, which may serve one or more users (not shown inFIG. 1).

In some demonstrative embodiments, wireless communication node101may communicate with the mobile devices of the first cell via a plurality of wireless communication links (“access links”). For example, wireless communication node101may communicate with mobile device140via a wireless access link103. Wireless access link103may include a downlink for communicating downlink data from wireless communication node101to mobile device140and/or an uplink for communicating uplink data from mobile device140to wireless communication node101.

In some demonstrative embodiments, backhaul links may be utilized for communication between the wireless communication nodes. For example, wireless communication node101may communicate with wireless communication node150via a wireless backhaul link119.

In some demonstrative embodiments, the backhaul links may be utilized for direct or indirect communication between the wireless communication nodes.

In some demonstrative embodiments, the backhaul links, e.g., backhaul link119, may include high-throughput links, which may be configured to communicate high throughput data between the wireless communication nodes.

In some demonstrative embodiments, the wireless backhaul links, e.g., wireless backhaul link119, may be utilized, for example, for systems including a relatively high density of nodes per area unit.

In some demonstrative embodiments, utilizing separate antenna systems at a node of system100for access and backhaul, e.g., one or more antenna arrays dedicated for communication over backhaul links and one or more other antenna arrays dedicated for communication over access links, may be beneficiary in some aspects. For example, utilizing separate antenna systems at a node for access and backhaul may limit interference in an environment, e.g., since directional antenna arrays may be utilized for directional backhaul links; and/or may enable using different types of antennas, for example, for forming the access and backhaul links in different frequency bands.

However, in some demonstrative embodiments, a node, e.g., a mmWave node, implementing separate antennas for access and backhaul, e.g., over the mmWave band, may be bulky, expensive, complex and/or inefficient.

In some demonstrative embodiments, one or more wireless communication nodes of system100, e.g., wireless communication node101, may utilize a common antenna array for communicating over both one or more backhaul links, e.g., backhaul link119, and one or more access links, e.g., access link103, as described below.

In other embodiments a device, e.g., a node or any other suitable device, may include a plurality of common antenna arrays, e.g., each configured to communicate over both the access and backhaul links.

In some demonstrative embodiments, high throughputs of the access links may require comparable high throughput backhaul links. Accordingly, it may be beneficiary to implement the backhaul links, e.g., backhaul link119, in the mmWave band as well.

In other embodiments the backhaul links may include wired links and/or wireless links. The wireless backhaul links may utilize one or more antenna arrays in common with the access links and/or one or more antenna arrays dedicated for the backhaul links.

In some demonstrative embodiments, one or more wireless communication nodes of system100, e.g., wireless communication node101, may be configured for providing enough range and flexibility for access and backhaul applications.

In some demonstrative embodiments, antenna array108may be configured to create multiple beams carrying different information. Accordingly, wireless communication node101may be configured to simultaneously communicate with a plurality of wireless communication nodes and/or mobile devices, e.g., utilizing a Multi-User (MU) Multi-Input-Multi-Output (MIMO) communication mode, e.g., as described below.

In some demonstrative embodiments, antenna array108may include an antenna array having a relatively increased antenna aperture for providing the range and the flexibility for communicating with the plurality of wireless communication nodes and/or the mobile devices. For example, antenna array108may include a large circular antenna array or a set of linear antenna arrays, configured to cover several sectors, e.g., covering an area around node101, to communicate, e.g., simultaneously, over backhaul link119and access link103.

In some demonstrative embodiments, antennas108may be configured to steer one or more narrow beams in different angles in at least two dimensions, e.g., in both elevation and azimuth.

In one example, wireless communication node101may communicate over access link103with mobile device140via a first beam at a first elevation angle and at a first azimuth angle, and over backhaul link119with wireless communication node150via a second beam at a second elevation angle and at a second azimuth angle.

In another example, wireless communication node101may communicate over access link103with mobile device140via the first beam at the first elevation angle and at the first azimuth angle, and over backhaul link119with wireless communication node150via a wired link.

In some demonstrative embodiments, wireless access link103may include a direct link, e.g., a P2P link, for example, to enable direct communication between node101and mobile device140.

In some demonstrative embodiments, wireless access link103may include a wireless communication link over the mmWave band, e.g., the DMG band.

In some demonstrative embodiments, nodes101and/or150, and/or mobile device140may perform the functionality of mmWave STAs, e.g., DMG stations (“DMG STA”). For example, nodes101and/or150, and/or mobile device140may be configured to communicate over the DMG band.

In some demonstrative embodiments, wireless access link103may include a wireless beamformed link.

In some demonstrative embodiments, wireless access link103may include a wireless gigabit (WiGig) link. For example, wireless access link103may include a wireless beamformed link over the 60 GHZ frequency band.

In other embodiments, wireless access link103and/or wireless backhaul link119may include any other suitable link and/or may utilize any other suitable wireless communication technology.

In some demonstrative embodiments, wireless communication unit110may control antennas108to form access link103with mobile device140.

In some demonstrative embodiments, wireless communication unit110may control antenna108to generate a directional beam118directed in a direction117to communicate via wireless access link103.

In some demonstrative embodiments, wireless communication unit110may be configured to communicate via one or more sectors of antenna array108. For example, wireless communication unit110may be configured to communicate via four sectors, e.g., a first sector, a second sector, a third sector, and/or a fourth sector, covering an area around node101, for example, an area of 360 degrees around node101, such that each sector covers an area of 90 degrees. For example, the first sector may cover an area between 0 and 90 degrees around node101, the second sector may cover an area between 90 and 180 degrees around node101, the third sector may cover an area between 180 and 270 degrees around node101, and/or the fourth sector may cover an area between 270 and 0 degrees around node101, e.g., as described below with reference toFIG. 2.

In one example, antenna array108may include a plurality of linear antenna arrays, e.g., four linear antenna arrays, configured to cover the four sectors. In another example, antenna array108may include a circular antenna array configured to cover the four sectors.

In some demonstrative embodiments, wireless communication unit110may be configured to control antennas108to steer beam118in a direction117corresponding to a sector of node101, e.g., the first sector, the second sector, the third sector, or the fourth sector, to communicate with mobile device140. For example, wireless communication unit110may control antennas108to communicate with mobile device140over access link103via the first sector of node101, e.g., by steering directional beam118in direction117between 0 and 90 degrees.

In some demonstrative embodiments, wireless communication unit110may control antenna108to steer directional beam118by configuring beamforming settings of antenna108.

For example, wireless communication unit110may configure the beamforming settings of antenna108by adjusting phase shifts to be applied to the antenna elements of antenna108. Adjusting the phase shifts may enable to determine and/or control a width, gain and/or direction of directional beam118, e.g., as described below.

In some demonstrative embodiments, wireless communication unit110may be configured to obtain and/or to monitor the beamforming settings of antennas108. For example, wireless communication unit110may monitor the beamforming settings of antennas108to reconfigure and/or to readjust the beamforming settings of antennas108.

In some demonstrative embodiments, wireless communication unit110may readjust and/or reconfigure the beamforming settings of antenna108, for example, if a quality of access link103is reduced, e.g., upon a movement of mobile device140.

In some demonstrative embodiments, wireless communication unit110may be configured to control and steer directional beam118based on a movement of mobile device140. For example, wireless communication unit110may steer directional beam118to a direction, e.g., if mobile device140is moving to the direction.

In some demonstrative embodiments, wireless communication unit110may be configured to track the movement of mobile device140and to steer directional beam118based on the movement, for example, to maintain the quality of link103.

In some demonstrative embodiments, wireless communication unit110may be configured to control and steer directional beam118in an azimuth angle and/or in an elevation angle with respect to node101. For example, wireless communication unit110may steer the azimuth angle of directional beam118, e.g., if device140moves clockwise or counterclockwise with respect to node101; wireless communication unit110may steer the elevation angle of directional beam118, e.g., if device140moves away from or towards node101; and/or wireless communication unit110may steer both the elevation angle and the azimuth angle of directional beam118, e.g., if device140moves upward or downward together with a clockwise or counterclockwise movement with respect to node101.

In some demonstrative embodiments, a user of mobile device140may move mobile device140from a first location to a second, e.g., different, location.

In some demonstrative embodiments, the first location may correspond to a coverage area of the first sector of antennas108, and the second location may correspond to a coverage area of a second, e.g., different, sector of antennas108.

In some demonstrative embodiments, link103may be handed over from the first sector to the second sector of antennas108(“inter-sector handover”), for example, if device140is moved from the coverage area of the first sector to the coverage area of the second sector.

In some demonstrative embodiments, the first location may be in a coverage area of a first node, e.g., node101, and the second location may be in a coverage area of a second, e.g., different, node, e.g., node150.

In some demonstrative embodiments, link103may be handed over from the first node to the second node (“inter-cell handover”), for example, if device140is moved from the coverage area of node101to the coverage area of node154.

Utilizing a handover procedure for handing-over link103between the first and second sectors and/or the first and second nodes may be time-consuming, e.g., due to the necessity in performing signal quality measurement and/or making a decision of the sector or node to which the mobile device should be associated. The delays for such handovers may reduce the throughput performance and/or may delay the handover procedure in a mmWave network using sectored antennas.

In some demonstrative embodiments, wireless communication unit110may be capable of predicting a timing of a potential handover and/or a potential handover candidate, e.g., a sector or a node, to which beamformed link103is to be handed over, e.g., as described below.

In some demonstrative embodiments, wireless communication unit110may determine a handover candidate for handing over mobile device140, based on at least one beamforming parameter of link103.

In one example, the handover candidate may include, for example, a candidate antenna sector of antennas108to be used for communicating with mobile device140, e.g., in an inter-sector handover.

In another example, the handover candidate may include, for example, a candidate node, e.g., node150, to which link103with mobile device140may be handed over, e.g., in an inter-cell handover.

In some demonstrative embodiments, the at least one beamforming parameter may include at least one directionality parameter corresponding to a directionality of link103.

In some demonstrative embodiments, the at least one directionality parameter may include at least one angle parameter of an azimuth angle of link103and an elevation angle of link103. For example, link103may be directed to an azimuth of seventy degrees clockwise from the north, and an elevation of thirty degrees with respect to the horizon, e.g., as described below with reference toFIG. 4.

In some demonstrative embodiments, wireless communication unit110may determine the handover candidate based on a direction of a change in the directionality parameter.

In one example, wireless communication110may determine the handover candidate to be a second sector of antennas108, in an inter-sector handover, for example, if the direction of change in the directionality parameter is directed towards the second sector, e.g., as described below with reference toFIG. 2.

In another example, wireless communication110may determine the handover candidate to be node150in an inter-cell handover, for example, if the direction of change in the directionality parameter is directed towards node150, e.g., as described below with reference toFIG. 3.

In some demonstrative embodiments, wireless communication unit110may determine at least one relative-placement parameter relating to a relative placement between node101and mobile device140based on the beamforming parameter.

For example, wireless communication unit110may determine a relative location of device140with respect to node101based on the directionality parameter of link103.

In some demonstrative embodiments, the relative-placement parameter may include at least one relative angle between node101and mobile device140.

In some demonstrative embodiments, the relative angle may include at least one angle of an azimuth angle and an elevation angle relative between node101and mobile device140.

In some demonstrative embodiments, wireless communication unit110may determine an estimated distance between node101and mobile device140based on the elevation angle, e.g., as described below with reference toFIG. 4.

In some demonstrative embodiments, wireless communication unit110may determine the handover candidate based on the estimated distance.

In one example, wireless communication unit110may determine the handover candidate to be a second, e.g., different, sector of node101, e.g., the second sector, for example, if the estimated distance is inside the boundaries of a coverage area of the second sector.

In another example, wireless communication unit110may determine the handover candidate to be another node, e.g., node150, for example, if the estimated distance exceeds the coverage area of node101.

In some demonstrative embodiments, wireless communication unit110may determine the handover candidate based on a change in at least one angle of link103.

In one example, wireless communication unit110may determine the second sector of node101, e.g., and not the third or fourth sectors, to be the handover candidate, for example, if the change in the azimuth angle of link103is directed towards the second sector, and the estimated distance is inside the boundaries of a coverage area of the second sector, e.g., as described below with reference toFIG. 2.

In another example, wireless communication unit110may determine node150, e.g., and not other wireless communication nodes, to be the handover candidate, for example, if the change in the azimuth angle of link103is directed towards node150and the estimated distance exceeds the coverage area of node101, e.g., as described below with reference toFIG. 3.

In some demonstrative embodiments, wireless communication unit110may be configured to utilize one or more metrics (“handover prediction metrics”) to predict, estimate and/or determine a time (“predicted handover time”), at which link103is to be handed over. The metrics may include or may be related to, for example, the at least one relative-placement parameter.

In some demonstrative embodiments, wireless communication unit110may estimate a handover time for performing the handover based on the beamforming parameter, e.g., as described below.

In some demonstrative embodiments, wireless communication unit110may estimate the handover time for performing the handover based on a rate of a change in the directionality of link103.

In some demonstrative embodiments, wireless communication unit110may estimate the handover time for performing the handover based on a rate of a change in at least one angle of link103.

In one example, wireless communication unit110may estimate the handover time between the first sector and the second sector of antennas108based on an angular velocity of an azimuth change of the azimuth angle of link103. For example, wireless communication unit110may calculate an angular velocity of the azimuth angle of link103and may estimate, based on the angular velocity, when link103is assumed to cross the border line between the first and second sectors of antennas108, e.g., as described below with reference toFIG. 2.

In another example, wireless communication unit110may estimate the handover time for handing-over mobile device140between node101and node150, e.g., based on an angular velocity of an elevation change of the elevation angle of link103. For example, wireless communication unit110may estimate a rate of change in a relative distance between mobile device140and node101based on the angular velocity of the elevation angle of link103. Wireless communication unit110may estimate when mobile device140is assumed to cross from a coverage area of node101to a coverage area of node150based on the estimated angular velocity, e.g., as described below with reference toFIG. 4.

In some demonstrative embodiments, wireless communication unit110may inform the other node, e.g., node150, that beamforming training may be performed between mobile device140and the other node.

In some demonstrative embodiments, wireless communication unit110may inform node150via backhaul link119about the handover process. In other embodiments, wireless communication unit110may inform node150via any other wired or wireless communication about the handover process. For example, wireless communication unit110may transmit to wireless communication unit152, e.g., via backhaul link119, handover information for handing over mobile device140to node150.

In one example, the handover information may include an identity of mobile device140, e.g., a MAC address of device140, or any other identification of mobile device140.

In some demonstrative embodiments, node101may communicate with node150information with respect to one or more parameters of resources required to establish a wireless beamformed link between node150and mobile device140, e.g., a time interval of the link, a frequency range of the link, and/or a time-frequency window of the link.

In some demonstrative embodiments, node101may inform mobile device140about the handover process via link103. For example, wireless communication unit110may transmit to device140handover information for handing over mobile device140to node150.

In one example, the handover information may include an identity of node150, e.g., a MAC address of node150, or any other identification of node150, and the one or more resources parameters to establish the wireless beamformed link between node150and mobile device140.

In some demonstrative embodiments, wireless communication unit110may initialize the handover of mobile device140to the handover candidate.

In some demonstrative embodiments, wireless communication unit110may initialize the handover of mobile device140between the first sector and the second sector, e.g., prior to mobile device140crossing the borderline between the first and second sectors.

In some demonstrative embodiments, wireless communication unit110may adjust and/or configure the beamforming settings of antenna108prior to mobile device140crossing the borderline between the first and second sectors. For example, wireless communication unit110may adjust the beamforming settings of antenna108from communicating via the first sector to communicating via the second sector.

In some demonstrative embodiments, wireless communication unit110may initialize the handover of mobile device140to node150, e.g., prior to mobile device140entering to the coverage area of node150.

In some demonstrative embodiments, wireless communication unit152may adjust and/or configure the beamforming settings of antennas154prior to mobile device140crossing the borderline between the coverage area of node101and the coverage area of node150. For example, wireless communication unit152may adjust beamforming settings of antennas154for communicating with mobile device140upon mobile device140entering the coverage area of node150.

In some demonstrative embodiments, predicting the handover time and/or the handover candidate may allow, for example, substantial reduction of the time required for performing the handover and/or substantial reduction of the computational effort required by a mobile device for performing the handover, thereby reducing, for example, a power consumption of the mobile device.

Reference is made toFIG. 2, which schematically illustrates an inter-sector handover scheme200, in accordance with some demonstrative embodiments.

In some demonstrative embodiments, inter-sector handover scheme200may be utilized by a wireless communication unit utilizing an antenna array208covering four sectors, denoted Sector 1, Sector 2, Sector 3 and Sector 4, to communicate with a mobile device240. For example, antenna208may perform the functionality of antennas108(FIG. 1), and/or mobile device240may perform the functionality of mobile device140(FIG. 1). In other embodiments, antenna array208may cover any other number of sectors, e.g., 3 sectors, 6 sectors, and the like.

As shown inFIG. 2, Sector 1 may cover an area between 0 and 90 degrees around antenna array208, Sector 2 may cover an area between 90 and 180 degrees around antenna array208, Sector 3 may cover an area between 180 and 270 degrees around antenna array208, and/or Sector 4 may cover an area between 270 and 0 degrees around antenna array208.

In some demonstrative embodiments, node101(FIG. 1) may utilize antenna array208to communicate with mobile device240via a directional beam217. For example, directional beam217may perform the functionality of directional beam118(FIG. 1).

As shown inFIG. 2, in one example, antenna array208may include a large circular antenna array209to communicate with mobile device240. For example, node101(FIG. 1) may utilize large circular antenna array209to direct beam217to one or more sectors of the four sectors.

As also shown inFIG. 2, in another example, antenna array208may include set of linear antenna arrays207to communicate with mobile device240. For example, each linear antenna array of the set of linear antenna arrays207may cover a sector of Sectors 1, 2, 3 and 4.

In some demonstrative embodiments, node101(FIG. 1) may keep track of a relative positioning between mobile device240and antenna208.

In some demonstrative embodiments, node101(FIG. 1) may monitor an azimuth angle, denoted α, of directional beam217representing an azimuth between mobile device240and antenna208.

In some demonstrative embodiments, node101(FIG. 1) may be configured to control the azimuth angle α of directional beam217, e.g., as described above.

In some demonstrative embodiments, node101(FIG. 1) may be capable of obtaining and monitoring the azimuth angle α, for example, from the beamforming settings used by node101(FIG. 1) to communicate with mobile device240.

In some demonstrative embodiments, node101(FIG. 1) may determine, e.g., based on the azimuth angle α, when mobile device240is about to move from a first sector (“the current sector”) to a second sector (“the new sector”).

In some demonstrative embodiments, node101(FIG. 1) may be configured to determine the identity of the new sector, e.g., based on the azimuth angle α.

In some demonstrative embodiments, node101(FIG. 1) may be capable of using the information regarding the new sector and a predicted handover time to prepare antenna array208, e.g., in advance, for communicating with mobile device240upon handover. For example, node101(FIG. 1) may prepare beamforming settings of a directional beam227for communicating with mobile device240upon handover of device240from Sector 1 to Sector 2.

As shown inFIG. 1, for example, node101(FIG. 1) may be communicating with mobile device240via directional beam217in Sector 1. By monitoring the azimuth angle α between node101(FIG. 1) and mobile device240, node101(FIG. 1) may predict a time at which mobile device240is predicted to move from the coverage area of Sector 1 into the coverage area of Sector 2. For example, node101(FIG. 1) may detect a change of the azimuth angle α from a first azimuth angle covered by Sector 1 towards a second azimuth angle covered by Sector 2.

In some demonstrative embodiments, node101(FIG. 1) may determine a rate of change of the azimuth angle, e.g., based on a relationship between the change in the azimuth angle and a time period during which the change in the azimuth angle is measured.

In some demonstrative embodiments node101(FIG. 1) may predict the handover time, at which mobile device240is predicted to move into the coverage area of Sector 2. Node101(FIG. 1) may prepare, e.g., in advance, a beamforming setting of directional beam227of Sector 2 to communicate with mobile device240.

Additionally or alternatively, in some demonstrative embodiments, node101(FIG. 1) may be configured to utilize the azimuth angle α to predict the inter-cell handover of mobile device240, e.g., as described below with reference toFIG. 3.

Reference is made toFIG. 3, which schematically illustrates an inter-cell handover scheme300for handing over a mobile device340within a multi-cell wireless communication system301, in accordance with some demonstrative embodiments.

In some demonstrative embodiments, system301may include a plurality of wireless communication nodes configured to form a plurality of cells, e.g., small cells, for communicating with one or more mobile devices. For example, system301may include a wireless communication node310to form cell311; a wireless communication node320to form cell321; and/or a wireless communication node330to form cell331. For example, wireless communication nodes310,320and/or330may perform the functionality of node101(FIG. 1).

In some demonstrative embodiments, wireless communication nodes310,320and/or330may include one or more BSs. However, in other embodiments, the wireless communication system may include, additionally or alternatively, any other type of wireless communication device, for example, a station, a node, an access point, a hot spot, a network controller, and the like.

In some demonstrative embodiments, wireless communication node310may be configured to communicate with one or more mobile devices within cell311via one or more first wireless communication access links; wireless communication node320may be configured to communicate with one or more mobile devices within cell321via one or more second wireless communication access links; and/or wireless communication node330may be configured to communicate with one or more mobile devices within cell331via one or more third wireless communication access links.

In some demonstrative embodiments, wireless communication nodes310,320and/or330may be configured to communicate with mobile device340over a wireless beamformed link. For example, mobile device340may perform the functionality of mobile device140(FIG. 1).

In some demonstrative embodiments, mobile device340may include a UE, for example, a Smartphone, a notebook, a laptop, and the like.

In some demonstrative embodiments, one or more elements of system301may utilize the mmWave communication band to provide wireless connectivity for a relatively large coverage area, e.g., a coverage area of cells311,321and/or331. In one example, elements of system301may be deployed, for example, in outdoor spaces, e.g., a street, a stadium, and the like, and/or large indoor areas, e.g., conference halls, and the like. For example, system301may include a large number of small cells, which may be deployed to cover the large coverage area.

In some demonstrative embodiments, wireless communication nodes310,320and/or330may be configured to form one or more wireless communication backhaul links for wirelessly communicating information, e.g., backhaul information, between wireless communication nodes310,320and/or330.

In one example, wireless communication node310may communicate with wireless communication node320over a wireless backhaul link312formed between node310and node320; wireless communication node320may communicate with wireless communication node330over a wireless backhaul link322formed between node320and node330; and/or wireless communication node330may communicate with wireless communication node310over a wireless backhaul link332formed between node330and node310.

As shown inFIG. 3, node310may communicate with mobile device340, which may be located within cell311, over a beamformed access link313.

In some demonstrative embodiments, node310may determine a direction between node310and mobile device340based on an azimuth angle315of link313.

In some demonstrative embodiments, node310may determine one or more angles between nodes310,320and/or330, for example, based on azimuth angles of the backhaul links312,322, and/or332. For example, node310may determine an azimuth angle between nodes310and320based on the azimuth angle of backhaul link312.

In some demonstrative embodiments, node310may determine a candidate node to which mobile device340may be potentially handed over, for example, based on the azimuth angle315of the mobile device, based on a rate of change of the azimuth angle315of the mobile device and/or based on a comparison between the azimuth angle of the mobile device and the azimuth angles of nodes310,320and/or330.

For example, as shown inFIG. 3, the azimuth angle315of the mobile device340may change in a direction317towards the azimuth angle of node320. Accordingly, node310may predict that the mobile device340may be expected to be handed over to node320. Node310may also be able to predict the expected handover time, for example, based on the rate of change of the azimuth angle315.

In some demonstrative embodiments, node310may utilize one or more additional or alternative handover prediction metrics to predict one or more aspects of a handover of the mobile device.

In one example, node310may utilize an elevation angle of mobile device340, to predict a handover of mobile device340, e.g., as described below.

Reference is made toFIG. 4, which schematically illustrates an estimation scheme400to estimate a distance417between a mobile device440and a wireless communication node410, in accordance with some demonstrative embodiments. For example, wireless communication node101(FIG. 1) may utilize estimation scheme400to estimate a distance between node101(FIG. 1) and mobile device140(FIG. 1).

In some demonstrative embodiments, node410may estimate distance417based on an elevation angle415of mobile device440.

In some demonstrative embodiments, node410may determine the estimated distance417, between node410and mobile device440, based on an elevation angle415of mobile device440, e.g., as follows:
D=h*ctg(alpha)  (1)
wherein h denotes a height414of a tower of node410, D denotes the estimated distance417, alpha denotes the elevation angle415, and ctg denotes the cotangent function.

Referring back toFIG. 3, in some demonstrative embodiments, node310may determine, based on the azimuth angle315and/or the elevation angle415(FIG. 4), whether the mobile device340is moving out of the coverage area of cell311of node310and towards the coverage area of another node, e.g., node320or node330.

For example, node310, may determine that mobile device340is moving towards the coverage area of cell321of node320, for example, if azimuth angle315changes in a direction towards node320and the elevation angle415(FIG. 4) indicates that mobile device340is moving out of the coverage area of cell311and into the coverage area of cell321of node320.

In some demonstrative embodiments, node310may determine that mobile device340is moving towards the coverage area of the other node, and the distance between node310and mobile device340, e.g., distance417(FIG. 4), is such that the mobile device340is likely to move into the coverage area of the other node.

In some demonstrative embodiments, node310may instruct the other node, e.g., node320, for example, via the backhaul link, e.g., backhaul link312, to perform antenna training with the mobile device340, e.g., in advance of the actual crossing over of mobile device340into the coverage area of cell321, for example, to speed up the handover process.

Following is a description of a modular antenna array, which may be utilized by one or more of the nodes ofFIGS. 1, 2, 3 and/or 4, in accordance with some demonstrative embodiments. In other embodiments, any other suitable antenna array may be used. For example, the modular antenna array may perform the functionality of antenna array108(FIG. 1) and/or antenna array208(FIG. 2). In some demonstrative embodiments, the modular antenna array may also perform shared MIMO and/or beamforming processing for a plurality of beams.

In some demonstrative embodiments, an antenna array may include a modular architecture configured to synthesize larger composite antenna arrays from smaller sub-array antenna modules. A combination of RF beamforming in the sub-array antenna modules and central beamforming between sub-array antenna modules implemented, e.g., in a baseband, an intermediate frequency and/or an RF chain, may provide, for example, increased beamforming capabilities, for example, in terms of beam width, gain, coverage and beam steering. The antenna array may be configured, for example, to operate in the mmWave region of the RF spectrum and, in particular, the 60 GHz region associated with the use of, for example, wireless personal area network (WPAN) and wireless local area network (WLAN) communication systems.

Reference is now made toFIG. 5, which schematically illustrates a modular antenna array500, in accordance with some demonstrative embodiments.

In some demonstrative embodiments, modular antenna array500may perform the functionality of antenna array108(FIG. 1).

In some demonstrative embodiments, modular antenna array500may include at least one antenna array507including a plurality of antenna elements517. The plurality of antenna elements517may be configured, for example, for creation of a highly directional antenna pattern. The plurality of antenna elements517may include, for example, about 16-36 antenna elements, or any other number of antenna elements, which may be placed in a predefined geometry. The plurality of antenna elements517may be configured to form a plurality of highly directive antenna patterns or beams, which may be steered by setting appropriate signal phases at antenna elements517, e.g., as described below.

In some demonstrative embodiments, antenna array507may include a plurality of antenna subarrays. For example, antenna array507may include a first antenna subarray535, and a second antenna subarray545. In other embodiments, antenna array507may include any other number of antenna subarrays, e.g., more than two antenna subarrays.

The phrase “antenna subarray” as used herein may relate to a group of antenna elements of the plurality of antenna elements517, which may be coupled, for example, to a common RF chain. In one example, antennas507may include an antenna array, which may be divided into a plurality of, e.g., independent subarrays, each capable of independently generating a directional beam. In another example, antennas507may include a plurality of different antenna arrays to generate a plurality of directional beams. In another example, antennas507may include two or more different antenna arrays. One or more of the different antenna arrays may be divided into two or more subarrays.

In some demonstrative embodiments, first antenna subarray535may include a first plurality of antenna elements of the plurality of antenna elements517configured to form a first directional beam537directed in a first direction539.

In some demonstrative embodiments, second antenna subarray545may include a second, e.g., different, plurality of antenna elements of the plurality of antenna elements517configured to form a second directional beam547directed in a second direction549.

Some demonstrative embodiments are described herein with respect to a modular antenna array, e.g., modular antenna array500, including two sub-arrays, e.g., antenna sub-arrays535and545, configured to form two directional beams. However, in other embodiments, the modular antenna array may include any other plurality of antenna-sub-arrays to form any other plurality of directional beams.

In some demonstrative embodiments, modular antenna array500may include a plurality of Radio Frequency (RF) chains configured to control the first and second pluralities of antenna elements of antenna subarrays535and545.

In some demonstrative embodiments, the plurality of RF chains may be coupled to the plurality of antenna subarrays. For example, modular antenna array500may include a first RF chain530connected to first antenna subarray535, and a second RF chain540connected to second antenna subarray545. In other embodiments, modular antenna array500may include any other number of RF chains coupled to the any other number of the plurality of antenna subarrays, e.g., more than two RF chains connected to more than two antenna subarrays.

In some demonstrative embodiments, RF chains530and/or540may include or may be included as part of a radio frequency integrated circuit (RFIC), which may be connected to antenna subarrays535and545through a plurality of feed lines518, which may be, for example, micro-strip feed lines.

In some demonstrative embodiments, the plurality of RF chains may enable processing of two or more independent RF signals, e.g., carrying different data. For example, RF chain530may process an RF signal531, and RF chain540may process an RF signal541.

In some demonstrative embodiments, RF chain530may include a plurality of phase shifters515configured to adjust the phases of the antenna elements of antenna subarray535. For example, a phase shifter of phase shifters515may be configured to adjust a corresponding antenna element of antenna subarray535.

For example, phases of the antenna elements of antenna subarrays535may be shifted, e.g., by phase shifters515, to provide a constructive and/or destructive interference, configured to change the beamforming scheme of antenna subarray535and to change the direction of directional beam537.

In some demonstrative embodiments, RF chain540may include a plurality of phase shifters514configured to adjust the phases of the antenna elements of antenna subarray545. For example, a phase shifter of phase shifters514may be configured to adjust a corresponding antenna element of antenna subarray545.

For example, phases of the antenna elements of antenna subarrays545may be shifted, e.g., by phase shifters514, to provide a constructive and/or destructive interference, configured to change the beamforming scheme of antenna subarray545and to change the direction of directional beam547.

Phase shifters515and/or514may be discrete, e.g., configured to rotate the phase of the antenna elements of antenna subarrays535and/or545to a limited set of values, for example, 0, ±π/2, and π, allowing only a relatively coarse beamforming for changing a direction of directional beams537and/or547.

In some demonstrative embodiments, RF chain530may include a summer/splitter block513coupled to phase shifters515and/or RF chain540may include a summer/splitter block512coupled to phase shifters514.

In some demonstrative embodiments, summer/splitter block513may include a splitter534, e.g., a multiplexer, configured to reproduce and split RF signal531between the antenna elements of antenna subarray535and to couple the reproduced signals of RF signal531to phase shifters515, e.g., when transmitting RF signal531via beam537.

In some demonstrative embodiments, summer/splitter block513may include a summer536configured to sum into RF signal531signals received from the antenna elements of antenna subarray535, e.g., when receiving RF signal531via beam537.

In some demonstrative embodiments, utilizing two or more RF chains may enable baseband processing of two or more independent signals, e.g., carrying different data, communicated via two or more directional beams. In contrast, utilizing a single RF chain may enable baseband processing of only one signal, e.g., even if a large number of antenna elements517are utilized.

In some demonstrative embodiments, modular antenna array500may include a baseband550configured to control antenna subarrays535and545to form directional beams537and547directed to directions539and549for communicating a MIMO wireless transmission.

In some demonstrative embodiments, baseband550may process input data521into the MIMO wireless transmission to be communicated utilizing a MIMO beamformed scheme, e.g., as described below.

In some demonstrative embodiments, input data521may include data to be communicated over one or more backhaul links, e.g., backhaul link119(FIG. 1), and one or more access links, e.g., access link103(FIG. 1).

Some demonstrative embodiments are described herein with reference to a wireless communication unit, e.g., modular antenna array500, configured to perform both transmission and reception of a MIMO beamformed communication. Other embodiments may include a wireless communication unit capable of performing only one of transmission and reception of a MIMO beamformed communication.

In some demonstrative embodiments, modular antenna array500may include a plurality of baseband (BB) to RF (BB2RF) converters interfacing between the plurality of RF chains and baseband550. For example, modular antenna array500may include BB2RF converters533interfacing between RF chain530and baseband550, and BB2RF converters543interfacing between RF chain540and baseband550. In other embodiments, modular antenna array500may include any other number of BB2RF converters connecting between baseband550and any other number of RF chains, e.g., more than two.

In some demonstrative embodiments, BB2RF converters533and/or543may include down-converters, configured to convert an RF signal into a baseband data signal, and to provide the baseband data signal to baseband550, e.g., if modular antenna array500receives the MIMO wireless transmission.

For example, BB2Rf converter533may include a down converter532configured to down-convert RF signal531into data signal527, and to provide data signal527to baseband550.

In some demonstrative embodiments, baseband to RF converters533and/or543may include up-converters, configured to convert a baseband data signal into an RF signal and to provide the RF signal to an RF chain, e.g., if modular antenna array500transmits the MIMO wireless transmission.

For example, BB2RF converter533may include an up-converter538configured to up-convert data signal527into RF signal531and to provide RF signal531to RF chain530.

In some demonstrative embodiments, modular antenna array500may include a controller522configured to control RF Chains535and545and baseband550to perform the coarse beamforming and/or the fine beamforming.

In some demonstrative embodiments, controller522may control antenna subarrays535and/or545utilizing a control signal528carrying the amount of phase shift to be applied to one or more phase shifters of phase shifters515and/or514.

In some demonstrative embodiments, the phase shift adjustments to phase shifters515may determine and/or control the beam width, gain and/or direction of directional beam537formed by antenna subarray535.

In some demonstrative embodiments, the phase shift adjustments to phase shifters514may determine and/or control the beam width, gain and/or direction of directional beam547forms by antenna subarray545.

In some demonstrative embodiments, each phase shifter of an antenna element of antenna subarrays535and/or545may perform a local phase adjustment to a signal to create a local phase distribution in a desired beam direction.

In some demonstrative embodiments, control signal528may include weighting coefficients, which may be generated and/or derived from controller522, configured to steer directional beams537and/or547.

In some demonstrative embodiments, controller522may provide via control signal528a first set of weighting coefficients to phase shifters515configured to form a local phase adjustment to one or more antenna elements of antenna subarray535, resulting in directing beam537to direction539.

In some demonstrative embodiments, controller522may provide via control signal528a second, e.g., different set of weighting coefficients, to phase shifters514configured to form a local phase adjustment to one or more antenna elements of antenna subarray545, resulting in directing beam547to direction549.

In some demonstrative embodiments, modular antenna array500may be configured to perform hybrid beamforming. The hybrid beamforming may include, for example, performing a coarse beamforming in RF chains530and/or540, e.g., using phase-shifters539and/or549; and fine beamforming in baseband550, e.g., as described below.

In one example, the coarse beamforming and the fine beamforming may be performed, for example, as part of a beamforming procedure for setting up a beamformed link.

In some demonstrative embodiments, modular antenna array500may utilize the two or more antenna subarrays to communicate via a composite directional beam. For example, modular antenna array500may utilize the two or more antenna subarrays to form a composite directional beam directed in a composite beam direction.

In some demonstrative embodiments, modular antenna array500may utilize antenna subarrays535and/or545to operate as a composite antenna array with increased beamforming capability to form the composite directional beam. For example, the composite antenna array may have greater beamforming capabilities compared to each one of subarrays535and/or545.

In one example, modular antenna array500may utilize the composite directional beam to communicate a high-gain directional communication. For example, modular antenna array500may utilize the composite directional beam for communicating data streams in a relatively large area, e.g., an outdoor area, a relatively large space, and/or for a distance greater than 50 meters.

The phrase “high-gain directional communication”, as used herein may relate to a wireless communication at a gain greater than 30 Decibel isotropic (dBi), e.g., utilizing a relatively narrow steerable beam.

In some demonstrative embodiments, modular antenna array500may be utilized by a Transmit (TX) side and a Receive (RX) side to form directional beam157between the TX and RX sides.

In some demonstrative embodiments, controller522may utilize antenna subarrays535and/or545to form the composite directional beam. For example, modular antenna array500may control antenna subarray535to form directional beam537in the composite direction, and antenna subarray545to form directional beam547in the composite direction such that the composite directional beam may be formed as a combination of directional beams537and/or547.

Some demonstrative embodiments are described herein with reference to a communication system, e.g., wireless communication system500, wherein both the TX side and the RX side utilize a plurality of antenna modules to communicate via a composite directional beam. However, other embodiments may be implemented with respect to systems configured to communicate any other communication, for example, systems in which only one of the TX and RX sides utilizes a plurality of antenna subarrays, e.g., to communicate via the composite directional beam. For example, one of the TX and RX sides may utilize an omni-directional antenna, and another one of the TX and RX sides may utilize a multi-array transceiver, e.g., modular antenna array500.

In some demonstrative embodiments, modular antenna array500may communicate data signal521via the composite directional beam formed by the combination of both directional beams537and547. For example, modular antenna array500may distribute the same data components of data signal521to both signals531and541, such that a data component of data signal521is communicated via both a first beamformed link formed by directional beam537generated by antenna subarray535in the composite direction, and a second beamformed link formed by antenna subarray545in the composite direction. Accordingly, the data component of data signal521may be communicated via the composite directional beam, which may be formed by a combination of directional beams537and547.

In some demonstrative embodiments, signal521may include data communicated via an access link, e.g., access link103(FIG. 1), and a backhaul link, e.g., backhaul link119(FIG. 1).

In some demonstrative embodiments, each of RF signals531and541may include a combination of the data communicated via the access link, e.g., access link103(FIG. 1), and the data communicated via the backhaul link, e.g., backhaul link119(FIG. 1).

In one example, signals531and541may include components of signal521communicated via the composite directional beam.

In another example, signals531and541may include components of signal521communicated via more than one, e.g., two composite directional beams.

In some demonstrative embodiments, controller522may determine the first and second set of weighting coefficients to form the composite directional beam in the composite direction.

In other embodiments, controller522may determine the first and second set of weighting coefficients to form the two composite directional beams.

In some demonstrative embodiments, modular antenna array500may utilize the two or more RF chains to perform beamformed diversity communication, e.g., as described below.

The phrase “beamformed diversity communication”, as used herein may relate to any communication utilizing a plurality of beams.

Some demonstrative embodiments are described herein with reference to a communication system, e.g., wireless communication system500, wherein both the TX side and the RX side utilize a plurality of antenna subarrays to communicate a MIMO transmission. However, other embodiments may be implemented with respect to systems configured to communicate any other diversity communication, for example, systems in which only one of the Tx and Rx sides utilizes a plurality of antenna subarrays, e.g., to form a Single-Input-Multi-Output (SIMO) and/or a Multi-Input-Single-Output (MISO) beamformed link. For example, one of the Tx and Rx sides may utilize an omni-directional antenna, and another one of the Tx and Rx sides may utilize a multi-array transceiver, e.g., modular antenna array500.

In some demonstrative embodiments, the fine beamforming may include diversity processing, e.g., MIMO processing, MISO processing and/or SIMO processing, at baseband550, in an intermediate frequency processor and/or in RF chains. For example, the MIMO processing may include, for example, closed-loop (CL) MIMO processing, Open Loop (OL) MIMO processing, Space-Block Code (SBC) MIMO processing, e.g., Space Time Block Code (STBC) MIMO processing, Space Frequency Block Code (SFBC) MIMO processing, and the like.

In some demonstrative embodiments, modular antenna array500may be utilized by a node to form one or more independent directional communication beams. In one example, modular antenna array500may be utilized by node101(FIG. 1) to form directional beam118(FIG. 1). In another example, modular antenna array500may be utilized by node101(FIG. 1) to form both directional beam118(FIG. 1) and a directional beam for communicating over backhaul link119.

In some demonstrative embodiments, a plurality of different signals may be communicated via a plurality of beamformed beams. Each beamformed beam, which corresponds to an antenna subarray of the plurality of antenna subarrays, may communicate a signal, for example, via a plurality of antenna elements of the antenna subarray.

For example, a first signal, e.g., signal527, may be communicated via directional beam537generated by antenna subarray535, and a second, e.g., different signal, for example, signal529, may be communicated via directional beam547generated by antenna subarray545.

Reference is now made toFIG. 6, which schematically illustrates a planar modular antenna array602, in accordance with some demonstrative embodiments. For example, planar antenna array602may perform the functionality of modular antenna array500(FIG. 5).

In some demonstrative embodiments, planar antenna array602may include a planar array of antenna modules630, e.g., arranged in a two-dimensional array. For example, antenna modules630may be arranged in one or more rows, e.g., two rows, and one or more columns, e.g., two columns.

In some demonstrative embodiments, an antenna module630may include a plurality of antenna elements617, e.g., including antenna elements517(FIG. 5).

In some demonstrative embodiments, antenna elements617of an antenna module630may be arranged in a two-dimensional array. For example, antenna elements617of the antenna module630may be arranged in one or more rows, e.g., two or more rows, and one or more columns, e.g., two or more columns.

In some demonstrative embodiments, antenna module630may also include an RF chain, e.g., RF chain530(FIG. 5) or RF chain540(FIG. 5), to control antenna elements617, e.g., as described above with reference toFIG. 5.

For example, antenna modules630may be controlled by a controller622via control links610. Controller622may be implemented, for example, as part of a BB650. For example, controller620may perform the functionality of controller522(FIG. 5) and/or BB650may perform the functionality of BB550(FIG. 5). Data links612may transfer data signals between BB650and modules630. For example, control links610may transfer control signals528(FIG. 5), and/or data links may transfer data signals527and/or529(FIG. 5).

In some demonstrative embodiments, the planar arrangement of antenna modules630and the planar arrangement of antenna elements617may be advantageous, for example, for beam steering in two dimensions, e.g., azimuth and elevation and/or any other dimensions.

In one example, planar modular antenna array602may perform the functionality of antenna108(FIG. 1). For example, node101(FIG. 1) may utilize the planar arrangement of antenna modules630and the planar arrangement of antenna elements617of antennas modules630to steer the elevation angle and/or the azimuth angle of directional beam118(FIG. 1).

Reference is now made toFIG. 7, which schematically illustrates a method of handover of a wireless beamformed link, in accordance with some demonstrative embodiments. For example, one or more of the operations of the method ofFIG. 7may be performed by a wireless communication system, e.g., system100(FIG. 1); a wireless communication node, e.g., node101(FIG. 1); and/or a wireless communication unit, e.g., wireless communication unit110(FIG. 1).

As indicated at block702, the method may include controlling an antenna array of a wireless communication node for communicating between a wireless communication node and a mobile device via a beamformed link. For example, wireless communication unit110(FIG. 1) may control antenna array108(FIG. 1) for communicating over access link103(FIG. 1) between wireless communication node101(FIG. 1) and mobile device140(FIG. 1), e.g., as described above.

As indicated at block704, the method may include determining a handover candidate for handing over the mobile device, based on at least one beamforming parameter of the beamformed link. For example, wireless communication unit110(FIG. 1) may determine a handover candidate for handing over mobile device140(FIG. 1), based on at least one beamforming parameter of beamformed link103(FIG. 1), e.g., as described above.

As indicated at block706, the method may include estimating a handover time for performing the handover based on the at least one beamforming parameter. For example, wireless communication unit110(FIG. 1) may estimate the handover time for performing the handover based on the at least one beamforming parameter of link103(FIG. 1), e.g., as described above.

As indicated at block707, estimating the handover time for performing the handover may include estimating the handover time based on a rate of a change in a directionality of the beamformed link. For example, wireless communication unit110(FIG. 1) may estimate the handover time for performing the handover based on the rate of change of an azimuth and/or elevation of directional beam118(FIG. 1), e.g., as described above.

As indicated at block708, determining the handover candidate may include determining another sector of the wireless communication node for an inter-sector handover of the mobile device. For example, wireless communication unit110(FIG. 1) may determine a sector of antennas108(FIG. 1) as the candidate for handing over mobile device140(FIG. 1), e.g., as described above.

As indicated at block710, determining the handover candidate may include determining another wireless communication node for an inter-cell handover of the mobile device. For example, wireless communication unit110(FIG. 1) may determine node150(FIG. 1) as the candidate for handing over mobile device140(FIG. 1), e.g., as described above.

As indicated at block712, determining the handover candidate may include determining the handover candidate based on at least one relative angle between the wireless communication node and the mobile device. For example, wireless communication unit110(FIG. 1) may determine the handover candidate based on azimuth angle315(FIG. 3) and/or elevation angle415(FIG. 4), e.g., as described above.

As indicated at block714, determining the handover candidate may include estimating a distance between the wireless communication node and the mobile device based on the relative angle, and based on the distance to determine the handover candidate. For example, wireless communication unit110(FIG. 1) may estimate the distance417(FIG. 4) based on elevation angle415(FIG. 4), and may determine the handover candidate, e.g., node320(FIG. 3), based on distance417(FIG. 4), e.g., as described above.

Reference is made toFIG. 8, which schematically illustrates a product of manufacture800, in accordance with some demonstrative embodiments. Product800may include a non-transitory machine-readable storage medium802to store logic804, which may be used, for example, to perform at least part of the functionality of wireless communication node101(FIG. 1), wireless communication unit110(FIG. 1), wireless communication nodes310,320and/or330(FIG. 3) and/or wireless communication node410(FIG. 4), and/or to perform one or more operations of the method ofFIG. 7. The phrase “non-transitory machine-readable medium” is directed to include all computer-readable media, with the sole exception being a transitory propagating signal.

EXAMPLES

The following examples pertain to further embodiments.

Example 1 includes an apparatus of wireless communication, the apparatus comprising a wireless communication unit to communicate between a wireless communication node and a mobile device via a beamformed link between the wireless communication node and the mobile device, the wireless communication unit is to determine a handover candidate for handing over the mobile device, based on at least one beamforming parameter of the beamformed link.

Example 2 includes the subject matter of Example 1 and optionally, wherein the at least one beamforming parameter comprises at least one directionality parameter corresponding to a directionality of the beamformed link.

Example 3 includes the subject matter of Example 2 and optionally, wherein the at least one directionality parameter comprises at least one angle parameter selected from the group consisting of an azimuth angle of the beamformed link and an elevation angle of the beamformed link.

Example 4 includes the subject matter of Example 2 or 3 and optionally, wherein the wireless communication unit is to determine the handover candidate based on a direction of a change in the directionality parameter.

Example 5 includes the subject matter of any one of Examples 1-4 and optionally, wherein the wireless communication unit is to determine at least one relative-placement parameter relating to a relative placement between the wireless communication node and the mobile device based on the beamforming parameter, and to determine the handover candidate based on the at least one relative-placement parameter.

Example 6 includes the subject matter of Example 5 and optionally, wherein the at least one relative-placement parameter comprises at least one relative angle between the wireless communication node and the mobile device.

Example 7 includes the subject matter of Example 6 and optionally, wherein the at least one relative angle comprises at least one angle selected from the group consisting of an azimuth angle and an elevation angle.

Example 8 includes the subject matter of Example 6 or 7 and optionally, wherein the wireless communication unit is to determine an estimated distance between the wireless communication node and the mobile device based on the relative angle.

Example 9 includes the subject matter of any one of Examples 1-8 and optionally, wherein the beamformed link comprises a beamformed link formed by a first sector of an antenna array of the wireless communication node, and wherein the handover candidate comprises a second sector of the antenna array for an inter-sector handover of the mobile device.

Example 10 includes the subject matter of Example 9 and optionally, wherein the wireless communication unit is to determine the second sector based on a change in at least one angle of the beamformed link.

Example 11 includes the subject matter of any one of Examples 1-8 and optionally, wherein the handover candidate comprises another wireless communication node.

Example 12 includes the subject matter of Example 11 and optionally, wherein the wireless communication unit is to inform the other wireless communication node that beamforming training is to be performed between the mobile device and the other wireless communication node.

Example 13 includes the subject matter of any one of Examples 1-12 and optionally, wherein the wireless communication unit is to estimate a handover time for performing the handover based on the at least one beamforming parameter.

Example 14 includes the subject matter of Example 13 and optionally, wherein the wireless communication unit is to estimate the handover time for performing the handover based on a rate of a change in a directionality of the beamformed link.

Example 15 includes the subject matter of Example 13 or 14 and optionally, wherein the wireless communication unit is to estimate the handover time for performing the handover based on a rate of a change in at least one angle of the beamformed link.

Example 16 includes the subject matter of any one of Examples 1-15 and optionally, wherein the wireless communication unit is to initialize the handover to the handover candidate.

Example 17 includes the subject matter of any one of Examples 1-16 and optionally, wherein the wireless communication node comprises a base station.

Example 18 includes the subject matter of any one of Examples 1-17 and optionally, wherein the beamformed link comprises a link over a millimeter-Wave (mmWave) frequency band.

Example 19 includes a system of wireless communication, the system comprising at least one wireless communication node to communicate with one or more mobile devices of a wireless communication cell, the wireless communication node comprising an antenna array; and a wireless communication unit to control the antenna array for communicating with a mobile device via a beamformed link, the wireless communication unit is to determine a handover candidate for handing over the mobile device, based on at least one beamforming parameter of the beamformed link.

Example 20 includes the subject matter of Example 19 and optionally, wherein the at least one beamforming parameter comprises at least one directionality parameter corresponding to a directionality of the beamformed link.

Example 21 includes the subject matter of Example 20 and optionally, wherein the at least one directionality parameter comprises at least one angle parameter selected from the group consisting of an azimuth angle of the beamformed link and an elevation angle of the beamformed link.

Example 22 includes the subject matter of Example 20 or 21 and optionally, wherein the wireless communication unit is to determine the handover candidate based on a direction of a change in the directionality parameter.

Example 23 includes the subject matter of any one of Examples 19-23 and optionally, wherein the wireless communication unit is to determine at least one relative-placement parameter relating to a relative placement between the wireless communication node and the mobile device based on the beamforming parameter, and to determine the handover candidate based on the at least one relative-placement parameter.

Example 24 includes the subject matter of Example 23 and optionally, wherein the at least one relative-placement parameter comprises at least one relative angle between the wireless communication node and the mobile device.

Example 25 includes the subject matter of Example 24 and optionally, wherein the at least one relative angle comprises at least one angle selected from the group consisting of an azimuth angle and an elevation angle.

Example 26 includes the subject matter of Example 24 or 25 and optionally, wherein the wireless communication unit is to determine an estimated distance between the wireless communication node and the mobile device based on the relative angle.

Example 27 includes the subject matter of any one of Examples 19-26 and optionally, wherein the beamformed link comprises a beamformed link formed by a first sector of the antenna array, and wherein the handover candidate comprises a second sector of the antenna array for an inter-sector handover of the mobile device.

Example 28 includes the subject matter of Example 27 and optionally, wherein the wireless communication unit is to determine the second sector based on a change in at least one angle of the beamformed link.

Example 29 includes the subject matter of any one of Examples 19-26 and optionally, wherein the handover candidate comprises another wireless communication node.

Example 30 includes the subject matter of Example 29 and optionally, wherein the wireless communication unit is to inform the other wireless communication node that beamforming training is to be performed between the mobile device and the other wireless communication node.

Example 31 includes the subject matter of Example 29 or 30 and optionally, wherein the wireless communication unit is to control the antenna array to communicate with the other wireless communication node via a beamformed backhaul link.

Example 32 includes the subject matter of any one of Examples 19-31 and optionally, wherein the wireless communication unit is to estimate a handover time for performing the handover based on the at least one beamforming parameter.

Example 33 includes the subject matter of Example 32 and optionally, wherein the wireless communication unit is to estimate the handover time for performing the handover based on a rate of a change in a directionality of the beamformed link.

Example 34 includes the subject matter of Example 32 or 33 and optionally, wherein the wireless communication unit is to estimate the handover time for performing the handover based on a rate of a change in at least one angle of the beamformed link.

Example 35 includes the subject matter of any one of Examples 19-34 and optionally, wherein the wireless communication unit is to initialize the handover to the handover candidate.

Example 36 includes the subject matter of any one of Examples 19-35 and optionally, wherein the wireless communication node comprises a base station.

Example 37 includes the subject matter of any one of Examples 19-36 and optionally, wherein the beamformed link comprises a link over a millimeter-Wave (mmWave) frequency band.

Example 38 includes a product including a non-transitory storage medium having stored thereon instructions that, when executed by a machine, result in controlling an antenna array of a wireless communication node for communicating between the wireless communication node and a mobile device via a beamformed link; and determining a handover candidate for handing over the mobile device, based on at least one beamforming parameter of the beamformed link.

Example 39 includes the subject matter of Example 38 and optionally, wherein the at least one beamforming parameter comprises at least one directionality parameter corresponding to a directionality of the beamformed link.

Example 40 includes the subject matter of Example 39 and optionally, wherein the at least one directionality parameter comprises at least one angle parameter selected from the group consisting of an azimuth angle of the beamformed link and an elevation angle of the beamformed link.

Example 41 includes the subject matter of Example 38 or 39 and optionally, wherein the instructions result in determining the handover candidate based on a direction of a change in the directionality parameter.

Example 42 includes the subject matter of any one of Examples 38-41 and optionally, wherein the instructions result in determining at least one relative-placement parameter relating to a relative placement between the wireless communication node and the mobile device based on the beamforming parameter, and determining the handover candidate based on the at least one relative-placement parameter.

Example 43 includes the subject matter of Example 42 and optionally, wherein the at least one relative-placement parameter comprises at least one relative angle between the wireless communication node and the mobile device.

Example 44 includes the subject matter of Example 43 and optionally, wherein the at least one relative angle comprises at least one angle selected from the group consisting of an azimuth angle and an elevation angle.

Example 45 includes the subject matter of Example 43 or 44 and optionally, wherein the instructions result in determining an estimated distance between the wireless communication node and the mobile device based on the relative angle.

Example 46 includes the subject matter of any one of Examples 38-45 and optionally, wherein the beamformed link comprises a beamformed link formed by a first sector of an antenna array of the wireless communication node, and wherein the handover candidate comprises a second sector of the antenna array for an inter-sector handover of the mobile device.

Example 47 includes the subject matter of Example 46 and optionally, wherein the instructions result in determining the second sector based on a change in at least one angle of the beamformed link.

Example 48 includes the subject matter of any one of Examples 38-45 and optionally, wherein the handover candidate comprises another wireless communication node.

Example 49 includes the subject matter of Example 48 and optionally, wherein the instructions result in informing the other wireless communication node that beamforming training is to be performed between the mobile device and the other wireless communication node.

Example 50 includes the subject matter of any one of Examples 38-49 and optionally, wherein the instructions result in estimating a handover time for performing the handover based on the at least one beamforming parameter.

Example 51 includes the subject matter of Example 50 and optionally, wherein the instructions result in estimating the handover time for performing the handover based on a rate of a change in a directionality of the beamformed link.

Example 52 includes the subject matter of Example 50 or 51 and optionally, wherein the instructions result in estimating the handover time for performing the handover based on a rate of a change in at least one angle of the beamformed link.

Example 53 includes the subject matter of any one of Examples 38-52 and optionally, wherein the instructions result in initializing the handover to the handover candidate.

Example 54 includes the subject matter of any one of Examples 38-53 and optionally, wherein the wireless communication node comprises a base station.

Example 55 includes the subject matter of any one of Examples 38-54 and optionally, wherein the beamformed link comprises a link over a millimeter-Wave (mmWave) frequency band.

Example 56 includes a method of wireless communication, the method comprising controlling an antenna array of a wireless communication node for communicating between the wireless communication node and a mobile device via a beamformed link; and determining a handover candidate for handing over the mobile device, based on at least one beamforming parameter of the beamformed link.

Example 57 includes the subject matter of Example 56 and optionally, wherein the at least one beamforming parameter comprises at least one directionality parameter corresponding to a directionality of the beamformed link.

Example 58 includes the subject matter of Example 57 and optionally, wherein the at least one directionality parameter comprises at least one angle parameter selected from the group consisting of an azimuth angle of the beamformed link and an elevation angle of the beamformed link.

Example 59 includes the subject matter of Example 57 or 58 and optionally comprising determining the handover candidate based on a direction of a change in the directionality parameter.

Example 60 includes the subject matter of any one of Examples 56-59 and optionally comprising determining at least one relative-placement parameter relating to a relative placement between the wireless communication node and the mobile device based on the beamforming parameter, and determining the handover candidate based on the at least one relative-placement parameter.

Example 61 includes the subject matter of Example 60 and optionally, wherein the at least one relative-placement parameter comprises at least one relative angle between the wireless communication node and the mobile device.

Example 62 includes the subject matter of Example 61 and optionally, wherein the at least one relative angle comprises at least one angle selected from the group consisting of an azimuth angle and an elevation angle.

Example 63 includes the subject matter of Example 61 or 62 and optionally comprising determining an estimated distance between the wireless communication node and the mobile device based on the relative angle.

Example 64 includes the subject matter of any one of Examples 56-63 and optionally, wherein the beamformed link comprises a beamformed link formed by a first sector of an antenna array of the wireless communication node, and wherein the handover candidate comprises a second sector of the antenna array for an inter-sector handover of the mobile device.

Example 65 includes the subject matter of Example 64 and optionally comprising determining the second sector based on a change in at least one angle of the beamformed link.

Example 66 includes the subject matter of any one of Examples 56-63 and optionally, wherein the handover candidate comprises another wireless communication node.

Example 67 includes the subject matter of Example 66 and optionally comprising informing the other wireless communication node that beamforming training is to be performed between the mobile device and the other wireless communication node.

Example 68 includes the subject matter of any one of Examples 56-67 and optionally comprising estimating a handover time for performing the handover based on the at least one beamforming parameter.

Example 69 includes the subject matter of Example 68 and optionally comprising estimating the handover time for performing the handover based on a rate of a change in a directionality of the beamformed link.

Example 70 includes the subject matter of Example 68 or 69 and optionally comprising estimating the handover time for performing the handover based on a rate of a change in at least one angle of the beamformed link.

Example 71 includes the subject matter of any one of Examples 56-70 and optionally comprising initializing the handover to the handover candidate.

Example 72 includes the subject matter of any one of Examples 56-71 and optionally, wherein the wireless communication node comprises a base station.

Example 73 includes the subject matter of any one of Examples 56-72 and optionally, wherein the beamformed link comprises a link over a millimeter-Wave (mmWave) frequency band.

Example 74 includes an apparatus of wireless communication, the apparatus comprising: means for controlling an antenna array of a wireless communication node for communicating between the wireless communication node and a mobile device via a beamformed link; and means for determining a handover candidate for handing over the mobile device, based on at least one beamforming parameter of the beamformed link.

Example 75 includes the subject matter of Example 74 and optionally, wherein the at least one beamforming parameter comprises at least one directionality parameter corresponding to a directionality of the beamformed link.

Example 76 includes the subject matter of Example 75 and optionally, wherein the at least one directionality parameter comprises at least one angle parameter selected from the group consisting of an azimuth angle of the beamformed link and an elevation angle of the beamformed link.

Example 77 includes the subject matter of Example 74 or 75 and optionally comprising means for determining the handover candidate based on a direction of a change in the directionality parameter.

Example 78 includes the subject matter of any one of Examples 74-77 and optionally comprising means for determining at least one relative-placement parameter relating to a relative placement between the wireless communication node and the mobile device based on the beamforming parameter, and determining the handover candidate based on the at least one relative-placement parameter.

Example 79 includes the subject matter of Example 78 and optionally, wherein the at least one relative-placement parameter comprises at least one relative angle between the wireless communication node and the mobile device.

Example 80 includes the subject matter of Example 79 and optionally, wherein the at least one relative angle comprises at least one angle selected from the group consisting of an azimuth angle and an elevation angle.

Example 81 includes the subject matter of Example 78 or 79 and optionally comprising means for determining an estimated distance between the wireless communication node and the mobile device based on the relative angle.

Example 82 includes the subject matter of any one of Examples 74-81 and optionally, wherein the beamformed link comprises a beamformed link formed by a first sector of an antenna array of the wireless communication node, and wherein the handover candidate comprises a second sector of the antenna array for an inter-sector handover of the mobile device.

Example 83 includes the subject matter of Example 82 and optionally comprising means for determining the second sector based on a change in at least one angle of the beamformed link.

Example 84 includes the subject matter of any one of Examples 74-81 and optionally, wherein the handover candidate comprises another wireless communication node.

Example 85 includes the subject matter of Example 84 and optionally comprising means for informing the other wireless communication node that beamforming training is to be performed between the mobile device and the other wireless communication node.

Example 86 includes the subject matter of any one of Examples 74-85 and optionally comprising means for estimating a handover time for performing the handover based on the at least one beamforming parameter.

Example 87 includes the subject matter of Example 86 and optionally comprising means for estimating the handover time for performing the handover based on a rate of a change in a directionality of the beamformed link.

Example 88 includes the subject matter of Example 86 or 87 and optionally comprising means for estimating the handover time for performing the handover based on a rate of a change in at least one angle of the beamformed link.

Example 89 includes the subject matter of any one of Examples 74-88 and optionally comprising means for initializing the handover to the handover candidate.

Example 90 includes the subject matter of any one of Examples 74-89 and optionally, wherein the wireless communication node comprises a base station.

Example 91 includes the subject matter of any one of Examples 74-90 and optionally, wherein the beamformed link comprises a link over a millimeter-Wave (mmWave) frequency band.