Biological tissue detection using differential beamforming in mobile communication systems

Abstract

The method includes transmitting a plurality of transmit beams via a first antenna array of the mobile communication device and receiving a plurality of receive beams via a second antenna array of the mobile communication device. Each beam pair of the plurality of beam pairs includes a respective transmit beam of the plurality of transmit beams and a respective receive beam of the plurality of receive beams. Then, based on a comparison between beam pairs of the plurality of beam pairs, it is determined whether an object is proximate to the mobile communication device. Then, in response to determining that an object is proximate to the mobile communication device, one or more transmit parameters are determined. Then, a signal is transmitted using the one or more transmit parameters.

Description

[Background technology]

[0001] Wireless communication systems may use radio frequency (RF) signals to transmit data from a transmitter to a receiver. For example, a transmitter may include an antenna system that outputs an RF signal, which propagates into surrounding space and is received by a receiver having an antenna system tuned to receive the RF signal. As the RF signal propagates from the transmitter to the receiver, it may interact with surrounding objects. Objects in close proximity to the antenna system are affected by the RF signal in various ways, with objects having a much more adverse effect on RF signal transmission than air. As a result, the objects may adversely affect device efficiency. In certain situations, objects in close proximity to the antenna system may absorb electromagnetic energy, resulting in a reduction in received signal strength. Summary of the Invention

[0002] Generally, the present disclosure is directed to devices and techniques for determining whether biological tissue is in proximity to an antenna system of a wireless device. The wireless communication system may use an RF transmitter electromagnetically coupled to a transmitting antenna system. The RF transmitter and transmitting antenna system may be configured to send electromagnetic energy to a receiving antenna system electromagnetically coupled to an RF receiver. As the physical distance between the transmitting antenna and the receiving antenna increases, the receiving antenna system may benefit from increasing the amount of transmitted energy from the transmitting antenna. Increasing the amount of transmitted energy may increase the strength of the electromagnetic field near the transmitting antenna. Increasing the amount of transmitted energy may accelerate the rate at which batteries used by mobile communication devices deplete energy. Being able to determine whether biological tissue is in proximity to the transmitting antenna allows the antenna system to respond by selecting an antenna associated with a more efficient transmission path, thereby requiring less transmit energy and conserving battery energy.

[0003] According to one or more aspects of the present disclosure, a device may determine whether biological tissue is present near the device's antenna system. For example, by simultaneously transmitting and receiving electromagnetic energy with a differential beamforming array, it is possible to ascertain whether biological tissue is present near the transmitting antenna system. Some embodiments of the present disclosure are directed to methods for detecting such tissue near a mobile communication device configured to use differential beamforming techniques implemented with an antenna array.

[0004] The mobile communication device may transmit transmit beams from the transmit antenna array. The mobile communication device may also receive receive beams received by the receive antenna array. Each transmit / receive beam pair may include a transmit beam and a receive beam. The mobile communication device may transmit electromagnetic energy in various transmit beams using the transmit / receive beam pairs. The electromagnetic energy may be reflected by various objects, causing the electromagnetic energy to propagate back toward the antenna array. The mobile communication device may receive the reflected electromagnetic energy in various receive beams using the transmit / receive beam pairs. If the mobile communication device determines that an object having the electromagnetic properties of living tissue is present near the transmit antenna array, it may adjust transmit parameters of subsequent transmissions.

[0005] By adjusting transmission parameters, a wireless communication system may effectively reduce the intensity of electromagnetic energy in a selective manner to comply with Specific Absorption Rate (SAR) requirements, improve channel quality between a transmitter and a receiver, and conserve electrical energy stored in a battery. In some embodiments, the transmission parameters may include parameters for adjusting transmit power or antenna gain pattern.

[0006] In one example, a method includes transmitting various transmit beams via a first antenna array of a mobile communication device and receiving various receive beams via a second antenna array of the mobile communication device, where each of the various beam pairs includes a respective transmit beam of the various transmit beams and a respective receive beam of the various receive beams. The method further includes determining whether biological tissue is proximate to the mobile communication device based on a comparison between beam pairs of the various beam pairs, and determining one or more transmit parameters in response to determining that biological tissue is proximate to the mobile communication device. The method further includes transmitting a signal with the one or more transmit parameters.

[0007] As another example, a mobile communication device includes a first antenna array configured to transmit various transmit beams. The mobile communication device also includes a second antenna array configured to receive various receive beams. Each of the various beam pairs includes a respective transmit beam of the various transmit beams and a respective receive beam of the various receive beams. The mobile communication device also includes one or more processors configured to determine whether an object is in proximity to the mobile communication device based on a comparison between beam pairs of the various beam pairs. The mobile communication device also includes a radio configured to determine one or more transmit parameters and transmit a signal using the one or more transmit parameters upon determining that an object is in proximity to the mobile communication device.

[0008] The details of one or more embodiments of the disclosure are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the disclosure will be apparent from the description and drawings, and from the claims. [Brief explanation of the drawings]

[0009] [Figure 1]FIG. 1 is a conceptual diagram illustrating an example of a wireless communication device configured to detect biological tissue in proximity to an antenna array of the wireless communication device, in accordance with one or more techniques of the present disclosure. [Figure 2] FIG. 1 is a conceptual block diagram illustrating an example of a millimeter-wave module that generates transmit and receive beams in accordance with one or more techniques of this disclosure. [Figure 3] 1A-C are conceptual diagrams of example antenna arrays used in mobile communication devices in accordance with one or more techniques of this disclosure. [Figure 4] FIG. 1 is a conceptual block diagram illustrating an example of a dual-polarized receiver used to process signals received on various receive beams in accordance with one or more techniques of this disclosure. [Figure 5] 10A-10C are conceptual graphs illustrating examples of differential power matrices plotted against multiple transmit beam identifiers in various environments, in accordance with one or more techniques of the present disclosure. [Figure 6] 1 is a conceptual flowchart illustrating an example of a method for detecting biological tissue in proximity to an antenna array of a mobile communication device, in accordance with one or more techniques of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0010] A mobile communication device or wireless communication device may be a digital device that transmits and receives data over a radio frequency (RF) link. The terms mobile communication device and wireless communication device may be used interchangeably and mean the same thing. A wireless communication system may refer to a second mobile communication device or to a more complex communication system such as a wireless base station, wireless router, or wireless relay. A mobile communication device may be in communication attempt with the wireless communication system. In some embodiments, the wireless communication system may be another mobile communication device, a base station, a wireless router, a wireless relay, or other wireless system capable of transmitting and receiving data over an RF link.

[0011] Some examples of mobile communication devices include a mobile phone, a wireless watch, wireless eyeglasses, a wireless pedometer, wireless headphones, and a wireless health sensor. The mobile communication device may output RF energy when transmitting data to another wireless communication system over an RF link. The mobile communication device may be configured to use an RF transmitter when outputting RF energy. The wireless communication device may receive RF energy when receiving data from another wireless communication system over an RF link. The wireless communication device may be configured to use an RF receiver when receiving RF energy. In some examples, the wireless communication device may be configured to output RF energy or receive RF energy even when not actively transmitting or receiving data. For example, as described in more detail below, transmitting and receiving RF energy may be useful for detecting a user's proximity to the mobile communication device.

[0012] In some wireless devices, a part of a user's body may be placed in proximity to the mobile communication device. External output peripherals may be integrated into the wireless device to interact with the user's senses. Some examples of external output peripherals include a display, a motor, a light-emitting diode (LED), a speaker, or other output peripherals. The output peripherals may communicate information using the user's senses (e.g., sight, smell, taste, touch, or hearing). Because the wireless device may use the user's senses to communicate information, the user may be in proximity to the wireless communication device. In some examples, the user may be holding the wireless communication device in contact with biological tissue (e.g., skin, hair, organs, or muscles) of the wearer. Because the wireless communication device may communicate wireless data to other wireless communication systems, the wireless communication device may transmit RF energy when the wireless communication device is in proximity to biological tissue. In some examples, the user may be holding the wireless communication device in contact with the wearer's skin when the mobile communication device transmits wireless data to other wireless communication systems.

[0013] In some embodiments, a mobile communication device may transmit wireless data to a wireless communication system that is physically far away. In some embodiments, the physical distance between the mobile communication device and the wireless communication system may not be reduced. As the distance between the wireless transmitting device and the wireless receiving device increases, the power density received by the wireless communication system decreases. If the power density is too low for the receiving wireless communication system, the wireless communication device may be unable to receive the data. To increase the power density in the wireless communication system, a transmitter on the mobile communication device may increase the electromagnetic energy intensity of the electromagnetic energy transmitted from the transmitter's antenna.

[0014] In some examples, a mobile phone may be a mobile communication device, and the base station may be a wireless communication system. The mobile phone may transmit data to a wireless base station located one to two miles away. In some examples, the mobile phone may transmit high-intensity electromagnetic energy so that a receiver on the base station receives a signal with sufficient power density. In some examples, when transmitting with high-intensity electromagnetic energy, a user's tissue may be in close proximity to the wireless communication device. According to one or more techniques of the present disclosure, when communicating with a base station far away from the mobile phone, the mobile phone may be held in the user's hand, requiring the mobile phone to output high-intensity electromagnetic energy. Outputting high-intensity electromagnetic energy may deplete a battery more quickly than average-intensity or low-intensity electromagnetic energy.

[0015] In some embodiments, when biological tissue is in close proximity to the antenna system, the antenna system may increase the intensity of the electromagnetic energy transmitted from the antenna system. Increasing the intensity of the electromagnetic energy transmitted from the mobile communication device increases the energy drawn from the battery, shortening the operating time between battery charges. Antenna gain may be manipulated to transmit a signal of higher energy density to the receiver without increasing the energy intensity of the transmitted signal. A phased array may be used to modify the antenna gain pattern of the antenna array. In some embodiments, modifying the antenna gain pattern by increasing the antenna gain in the direction of the receiver and decreasing the antenna gain in the direction of human tissue may prevent the mobile communication device from increasing its signal strength while maintaining or improving channel quality. Preventing the mobile communication device from increasing its signal strength may extend the operating time per battery charge or improve the communication path.

[0016] According to one or more techniques of the present disclosure, a device may determine whether biological tissue is present near a transmitting antenna system of the device. For example, by simultaneously transmitting and receiving electromagnetic energy with a differential beamforming array, it may be possible to determine whether biological tissue is present near the antenna system. Some embodiments of the present disclosure are directed to methods for determining whether such tissue is present near a wireless communication device using differential beamforming implemented with an antenna array.

[0017] 1 is a conceptual diagram illustrating an example of a wireless communication device 100 configured to detect biological tissue 112 proximate to an antenna array 106 or 102 of the wireless communication device, in accordance with one or more techniques of the present disclosure. Some examples of the wireless communication device 100 include a mobile phone, which may transmit data to and receive data from a second wireless communication device. In some examples, the second wireless communication device may be a base station. In some examples, the base station may be remote from the wireless communication device (e.g., up to about 3, 4, 5, or 6 miles away).

[0018] In some embodiments of FIG. 1, the wireless communication device 100 may utilize a method for detecting whether biological tissue 112 (e.g., a human hand, a human head, a human body, or a substance having the characteristics of human tissue) is in proximity to the mobile communication device 100. The mobile communication device may transmit energy from multiple transmit beams using a transmit array. The transmitted energy may be reflected by a nearby object, such as biological tissue. Upon reflection by the object, the electromagnetic energy may propagate back to the mobile communication device. A receive antenna array used by the mobile communication device may receive the energy using multiple receive beams. In some embodiments, each transmission of a transmit beam may be received by a selected receive beam. A receive beam may be selected by the wireless communication device to receive the reflected energy. In some embodiments, a beam pair may include a transmit beam that generates a transmission and a receive beam that receives a transmission. Each beam pair of the multiple beam pairs includes a respective transmit beam of the multiple transmit beams and a respective receive beam of the multiple receive beams.

[0019] In some embodiments of FIG. 1 , the wireless communication device may compare energy transmitted and received between beam pairs of the plurality of beam pairs. The wireless communication device may determine whether biological tissue is in proximity to the mobile communication device based on the comparison. In some embodiments, the comparison includes comparing received power from the reflected energy to a threshold value. The threshold value may be a value determined through testing and / or calibration. In some embodiments, received power below the threshold value may indicate that human tissue is not present or that human tissue is far enough from the transmit beam so as not to significantly affect the signal power density at the receiver. A received power level above the threshold value may indicate that biological tissue is present or in proximity to the transmit beam. When biological tissue is present or in proximity to the transmit beam, the electromagnetic energy density received by the receiver may be too low to be detected without increasing the transmit power. A received power level above the threshold value may indicate that electromagnetic energy is not being transmitted efficiently to the receiver. Specifically, to improve signal quality of communications with a remote device (e.g., as measured by a received signal strength indicator (RSSI)), electromagnetic force strength can be reduced by reconfiguring the transmit beam away from tissue without increasing transmit power, thereby conserving battery life.

[0020] In some examples of Figure 1, upon determining that biological tissue is in proximity to the mobile communication device, the mobile communication device may respond by determining one or more transmission parameters and transmitting a signal based on the one or more transmission parameters. In some examples, the transmission of the signal may be performed using the one or more transmission parameters.

[0021] In some embodiments of FIG. 1 , wireless communication device 100 may be a smartphone, tablet, laptop, wireless reader, wireless headphones, smartwatch, or other body-worn wireless communication device. Other body-worn wireless communication devices may include any device in close proximity to the body (e.g., within less than a few feet) that transmits RF, millimeter-wave, or micrometer-wave electromagnetic signals using a periodically recharged battery. Mobile communication devices may use various wireless communication techniques. Some embodiments of mobile communication device 100 may utilize wireless communication protocols, such as mobile communication techniques. Some mobile communication techniques include 3G, 4G, 5G, and / or 6G communication technologies. These include Global System for Mobile Communications (GSM), Frequency Division Multiplexing (FDM), Time Division Multiple Access (TDMA), Orthogonal Frequency Division Multiplexing (OFDM), and Multiple Input Multiple Output (MIMO).

[0022] In some embodiments of FIG. 1, the mobile communication device 100 may include a transmitter having a transmit antenna array 102 and a receiver having a receive array 106. In some embodiments, the transmit array 106 may be configured to transmit multiple transmit beams. In some embodiments, the receive array 106 may be configured to receive with multiple receive beams. When the transmit array and the receive array are separate arrays, the first array may be designated as the transmit array and the second array may be designated as the receive array. The transmit array may be an array of antenna elements arranged on a dedicated transmit antenna array printed circuit board (PCB). The receive array may be an array of antenna elements arranged on a dedicated receive antenna array printed circuit board (PCB). In some embodiments, the first array may be an array of antenna elements arranged on a phased array beamforming integrated chip (IC). The second array may be an array of antenna elements arranged on a phased array beamforming integrated chip (IC).

[0023] 1, the transmit array 106 and the receive array 102 may be part of a millimeter-wave module. Using the millimeter-wave module, the transmit array may be configured to transmit multiple transmit beams. In some embodiments, using the millimeter-wave module, the receive array may be configured to receive multiple receive beams. The millimeter-wave module may be controlled by a processor within the mobile communication device.

[0024] In some embodiments, the transmit array 106 and the receive array 102 may be configured to generate a transmit beam 104 and a receive beam 108. The transmit beam 104 and the receive beam 108 may include multiple gain pattern antenna lobes. Some of the antenna lobes may be side lobes. In some embodiments, these antenna lobes may be generated by configuring the antenna array 102 or 106 to create antenna nulls. An antenna null is an angular position in the antenna gain pattern where the antenna gain is significantly below the gain value at angular positions near the null location. Some nulls may separate the antenna beam into multiple beams. In some embodiments, the null may be located at the center of a main beam and split the main beam into multiple beams. Some embodiments may include creating nulls along portions of the propagation path where destructive interference occurs by configuring the antenna array to transmit destructively interfering signals.

[0025] In some embodiments of FIG. 1 , the mobile communication device 100 may transmit a signal using transmit parameters 114. In some embodiments, the transmit parameters may include parameters related to the transmit power density of the transmission. Some examples of transmit parameters include transmit beam selection, transmit power level, modulation type, transmit duration, and transmit radio selection. In some embodiments, the transmit parameters may be used to monitor the presence of biological tissue. In some embodiments, the transmit parameters 114 may be used to reduce the electromagnetic power density of the transmission, thereby preserving the operating time of a single battery charge. In some embodiments, when the mobile communication device is simultaneously transmitting and receiving, the transmit parameters may be used to reduce self-jamming power reflected from biological tissue and received by the mobile communication device.

[0026] 2 is a conceptual block diagram illustrating an example of a millimeter-wave module that generates transmit and receive beams in accordance with one or more techniques of this disclosure. In some examples, the millimeter-wave module 200 may include the transmitter 210 and receiver 212 used in the mobile communication device 100 of FIG. 1. The transmitter 210 may further include a transmitter processor 230. The transmitter processor 230 may be configured to generate multiple signals. Each signal is transmitted through a unique channel 250. Each channel is connected to a separate amplifier 232, then to a separate phase shifter 234, and then terminated at a separate element of the antenna array 236. In some examples, a dual-polarized antenna array may be used. When a dual-polarized antenna is used, two channels may be directed to the same antenna element. When a non-polarized antenna array is used, each channel may be electromagnetically connected to its own dedicated antenna element.

[0027] In some embodiments of FIG. 2 , receive beam 248 may be generated by antenna array 246. Each element in antenna array 246 may receive a unique copy of the incoming signal. Each antenna element may transmit a copy of the signal through a channel path connected to the antenna element. The channel path may be one of multiple channel paths 260. Each channel path may include a phase shifter 244 and an amplifier 242. All channels may terminate in receiver post-processor 240. The receiver post-processor may digitize and correlate the signals received on multiple receive channels 260. Using the results of the digitized and correlated data, the receiver post-processor may generate two output data streams 214 and 216. Data streams 214 and 216 may be further processed by one or more processors within the mobile communication device according to one or more techniques of this disclosure.

[0028] In some embodiments, the transmitter processor 230 may include one or more signal generators configured to transmit phase-shifted copies of the same signal through the various channels 250. Furthermore, the transmitter processor may transmit coherent signals through the same path and modify the signal in each channel 250 using various analog amplifiers 232 and analog phase shifters 234. In some embodiments, the transmitter processor may also modify the amplitude of signals traveling through multiple channels 250. Furthermore, in other embodiments, the amplitude modification may be adjusted using analog amplifiers 232. Some embodiments of the present disclosure include the use of a digital-to-analog converter (DAC) in the transmitter processor. The DAC is configured to receive digital data representing a digital signal as an input and output an analog signal. The DAC may not have sufficient voltage swing to generate a signal with sufficient gain. In some embodiments, the DAC is a low-power DAC, and the amplification and phase shifting may be performed by external amplifiers 232 and phase shifters 234, respectively.

[0029] In some embodiments, amplifier 232 may include a power amplifier. In embodiments where an external power amplifier is used instead of a digital amplifier, the power amplifier may take various forms. In some embodiments, power amplifier 232 may include a distributed power amplifier with transmission lines and semiconductor switches. Power amplifiers may also be integrated on an integrated chip (IC). Power amplifiers may also be fully integrated into a module or package that connects to multiple channels 250 via a printed circuit board (PCB), wires, transmission lines, waveguides, twisted pairs, or other signal distribution methods. Power amplifiers of the same design may have some gain variation due to manufacturing and deployment variations. Furthermore, the gain of a power amplifier may not be easily adjustable. Thus, in some embodiments, the power amplifier may also incorporate various adjustable gain attenuators.

[0030] In some embodiments, an adjustable gain attenuator (not shown in FIG. 1 ) may be incorporated into the amplifier. The adjustable attenuator may configure the amplifier with wire range and gain setting accuracy that may be achievable with a power amplifier alone. Additionally, the adjustable gain attenuator may be incorporated into the transmitter processor 230 as an adjustable gain attenuator or as firmware (FW) and used to control the amplitude of the signal generated by the integrated DAC. The adjustable gain attenuator and power amplifier may also have some phase delay variation. This phase delay variation may be compensated for by the transmit phase shifter 234.

[0031] In further embodiments, the transmit phase shifter 234 may serve various purposes. One purpose may be to calibrate undesired phase delay due to variations in transmit components. Several components, including the power amplifier 232, the transmitter processor 230, and the antenna elements (e.g., the antenna elements of the transmit array 236), may cause undesired phase delay. Another purpose of the phase shifter may be to manipulate the phase front generated by the transmit antenna array 236. The transmit antenna array 236 may generate a phase front by combining electromagnetic signal contributions from multiple antenna elements. Because the contributions occur simultaneously, the antenna array may generate transmit beams with main lobes pointing in different directions based on the manipulation of the phase shifter 234.

[0032] In FIG. 2 , the receive phase shifter 244 may serve various purposes. One purpose may be to calibrate undesired phase delay due to variations in receive components. Several components, including the low-noise amplifier 242, the receiver post-processor 240, and antenna elements (e.g., antenna elements of the receive array 246), may cause undesired phase delay. Another purpose of the phase shifter may be to manipulate the phase plane of the receive antenna array 246. The receive antenna array 246 may generate receive beams configured to receive electromagnetic signals having a specific phase plane. The receive antenna array may receive electromagnetic waves from the phase planes arriving in various directions. The receive phase shifter may be used to delay specific copies of the electromagnetic waves received by specific receive antenna elements in the receive array 246. The receiver post-processor may then combine the phase-shifted copies to reconstruct the signal received by a specific receive beam. In some embodiments, the receive phase shifter may delay specific copies of the electromagnetic signal passing through specific channels of the multiple channels 260 to compensate for subsequent delays from receive components, such as the amplifier 242.

[0033] In some embodiments, amplifier 242 may include a low-noise amplifier (LNA). In embodiments where an LNA is used instead of a digital amplifier, the LNA may take various forms. In some embodiments, LNA 242 may include a distributed LNA with transmission line and semiconductor switch components. The LNA may also be integrated on an IC. The LNA may further be integrated into a module or package and connected to multiple channels 260 via PCB, wire, transmission line, waveguide, twisted pair, or other signal distribution methods. Even LNAs of the same design may have varying gain due to manufacturing and deployment variations. The gain of an LNA may not be easily adjustable. Thus, in some embodiments, the LNA may also incorporate various adjustable gain attenuators before connecting to receiver post-processor 240.

[0034] In some embodiments of the receiver post-processor 240, the post-processor may include the use of an analog-to-digital converter (ADC) in the receiver post-processor. The ADC is configured to receive an analog signal as an input and periodically sample the voltage of the input signal to convert the result into a digital representation of the signal. The periodic voltage samples are represented as a stream of digital data. The ADC may only sample electrical input signals having a periodic frequency less than half the ADC's sampling rate. Furthermore, the ADC may be limited to the voltage range it can measure on the electrical input signal. The ADC may also be limited by quantization error, i.e., error resulting from representing electrical measurements as discrete values. Each receive channel 260 may have its own ADC. Each ADC may generate a digital data stream, which is further processed by the receiver post-processor. The receiver post-processor may combine the digital data streams into a power measurement data stream 214 from the vertical polarization of the receive beam 248 and a power measurement data stream 216 from the horizontal polarization of the receive beam 248 after accounting for and compensating for various ADC errors. A process performed by the mobile communications device may use the vertical power measurement data stream 214 and the horizontal power measurement data stream 216 to determine whether biological tissue is in proximity to the antenna array.

[0035] 3A-3C are conceptual diagrams of example antenna arrays 310, 320, and 330 used in a mobile communication device in accordance with one or more techniques of the present disclosure. In some examples, the antenna arrays 310, 320, and 330 may be comprised of multiple antenna elements 312. The antenna elements 312 may be rectangular patch antennas, circular patch antennas, monopole antennas, dipole antennas, fractal antennas, planar inverted-F (PIFA) antennas, or other antenna topologies. The antenna elements may be constructed from conductive materials such as copper, silver, gold, or other conductive metals. The conductive metal may be plated onto a dielectric substrate 314 such as a PCB, silicon IC, or flexible polymer. Each element may be connected to its own channel (e.g., a receive channel or a transmit channel) via an antenna feed. In some examples, the antenna feed may provide continuity through adjacent conductive traces. Some examples of antenna feed configurations provide continuity between the circuit and the antenna elements. Some examples of feed mechanisms that provide continuity include conductive via connections 316 and 318, conductive traces, or wirebond connections. In some embodiments, the antenna feed may be a non-continuous electromagnetic connection mechanism. The non-continuous electromagnetic connection mechanism may include a slot, a capacitor, a waveguide, or other mechanism used to excite electromagnetic modes of the antenna. Depending on the orientation of the antenna feed, different electromagnetic modes of the antenna elements may be excited, resulting in different antenna polarization characteristics.

[0036] In some embodiments of FIG. 3A , the antenna elements may be fed with different orientations to elicit different polarization characteristics. In some embodiments, the conductive via holes 316 may be oriented to excite an electromagnetic mode in the antenna element that generates horizontally polarized electromagnetic waves. In some embodiments, the conductive via holes 318 may be oriented to excite an electromagnetic mode in the antenna element that generates vertically polarized electromagnetic waves. In some embodiments, the antenna elements in the antenna array 310 may be configured as dual-polarized antenna elements. Multiple transmit beams may be generated from a first antenna array using multiple dual-polarized antenna elements electromagnetically connected to multiple channels. A mobile communication device may include a first antenna array and a second antenna array. In some embodiments, the first antenna array comprises multiple transceivers electrically connected to the dual-polarized antenna elements. In some embodiments, the second antenna array may comprise multiple transceivers electrically connected to the dual-polarized antenna elements.

[0037] In some embodiments, the first antenna array and the second antenna array may be included in a single antenna array. The single antenna array may have multiple antenna elements. Multiple antenna elements may be configured as transmit elements and separate multiple elements may be configured as receive elements. In some embodiments, the single antenna array may be configured to simultaneously generate both multiple transmit beams and multiple receive beams.

[0038] In the example of FIG. 3B, several receive elements 322 may be arranged together on one portion of the array, and several transmit elements 324 may be arranged together on another portion of the array. Arrangement may mean that all of the transmit elements are arranged in a particular contiguous group. In some examples, all of the transmit elements may be arranged in a particular contiguous group. In some examples, all of the receive elements may be arranged in a particular contiguous group.

[0039] In the embodiment of FIG. 3C, some transmit elements 332A-D may be intermixed with some receive elements 334A-D in the array 330. Intermixing elements may reduce the amount of separation between the transmit and receive antenna elements. Reduced separation may result in reduced detection capabilities. Separation may be increased by using orthogonal polarization between adjacent elements. Separation may also be increased by using metamaterials between antenna elements.

[0040] In further embodiments of Figures 3A-3C, the antenna array 310, 320, or 330 may be reconfigurable as a transmit / receive array. In some embodiments of Figure 3B, the reconfigurable transmit / receive array may comprise multiple elements, each of which may be configured as a receive element or a transmit element. In some embodiments, elements configured as transmit elements together form a transmit array, and elements configured as receive elements together form a receive array. In some embodiments shown in Figure 3A, the entire reconfigurable transmit / receive array may be reconfigured as a transmit array or a receive array. This allows the complete array of elements to be configured as transmit antenna elements or receive antenna elements.

[0041] In some embodiments, the antenna arrays 310, 320, or 330 may be configured to generate antenna beams, such as the transmit beam 104 of FIG. 1 and the receive beam 108 of FIG. 1. The beams may be similar in shape to the gain patterns of the respective antenna arrays. The gain pattern of an antenna array is a three-dimensional pattern created by taking all points across multiple spatial locations where the antenna array produces the same gain. The antenna gain pattern is a conceptual idea that indicates where in space the antenna radiates its maximum power. In some embodiments, the transmit or receive beams generated by a large antenna array may have a very narrow beamwidth. A narrow beamwidth means that the antenna radiates a significant amount of power over a narrow angular range. A receiver located outside that angular range receives significantly less power than if the receiver were located within the narrow beamwidth of the main beam. Being outside the main beam makes it more difficult for the receiver to receive energy from the transmit beam in the receive beam.

[0042] In some embodiments, the antenna arrays 310, 320, and 330 may comprise multiple antenna elements. The design of the antenna array may be determined based on several considerations, including the physical antenna space, the dielectric material of the antenna substrate, the frequency bandwidth of operation, and the center frequency of the antenna. The number of elements in the antenna array may be determined based on the dielectric content of the board substrate 314 and the permittivity and conductivity of the surrounding materials. The physical size of the antenna elements may be determined based on the center frequency of operation. All elements in the antenna array may be electromagnetically spaced relative to one another. In some embodiments, groups of antenna elements may be electromagnetically connected together. These groups of antenna elements may have a combination that includes up to all of the elements in the array. These aspects of the array, along with many other aspects, consider how the array affects the gain of the multiple transmit beams 104 and the multiple receive beams 108.

[0043] In some embodiments, antenna gain affects the amount of electromagnetic energy that can be reflected by electromagnetic materials (e.g., biological tissue and materials with electromagnetic properties similar to biological tissue) in proximity to the antenna array. In some embodiments, antenna gain can also affect how a mobile communication device can transmit with one or more transmission parameters. In some embodiments, a high-gain antenna can generate transmit or receive beams with narrow beamwidths. A narrow beam can generate a stronger transmission link between a transmitter and a receiver. It can be observed that narrow beamwidths are directed away from adjacent tissue, resulting in less loss of the electromagnetic channel due to obstacles. Thus, at a given transmit power level, selecting a transmit beam directed away from biological tissue can be observed to provide better performance.

[0044] In some embodiments of FIGS. 3A-3C, the antenna beams generated by the antenna arrays 310, 320, and 330 may have various characteristics. In some embodiments, the antenna beams may be characterized by a beamwidth. The beamwidth may be defined as the half-power beamwidth (HPBW). The HPBW is the angle at which the gain pattern of the antenna beam transmits or receives half (e.g., 3 dB) of the power transmitted to or received by the antenna beam. In some embodiments, the antenna beamwidth may be a pencil beam with an HPBW of only 1-3 degrees. In other embodiments, the antenna beamwidth may be 360 ​​degrees, i.e., omnidirectional. In some embodiments, the antenna beamwidth may have an HPBW between a pencil beam pattern and an omnidirectional beam pattern.

[0045] In some embodiments of FIGS. 3A-3C, the antenna beams may have polarization characteristics. Polarization is defined as the orientation relationship of the electric field vector to the propagation vector in the far-field. Vertical polarization means that when a wave propagates tangentially to the Earth's surface, the electric field oscillates up and down perpendicular to the Earth's surface. Horizontal polarization means that when a wave propagates tangentially to the Earth's surface, the electric field oscillates left and right tangentially to the Earth's surface. A first antenna beam configured with one polarization may receive limited energy transmitted by a second antenna configured with an orthogonal polarization. One exception may occur when the transmit beam radiates energy that is reflected by an object, such as biological tissue. In some embodiments, a transmit beam configured to transmit with a first polarization may transmit energy that is reflected by the object. The transmitted energy may change polarization when reflected back with a second polarization orthogonal to the first polarization. The second polarization may be measured with a receive beam configured to receive the second polarization.

[0046] 4 is a conceptual block diagram illustrating an example of a dual-polarized receiver used to process signals received in various receive beams in accordance with one or more techniques of this disclosure. In some examples, an antenna array 312 generates various receive beams for receiving electromagnetic signals. The receive beams may include all of the antenna gain characteristics of the transmit beams. One difference between the transmit beams and receive beams is that the receive beams are received by an antenna or antenna array operably connected to the receiver. In comparison, the transmit beams generated by the antenna or antenna array are operably connected to the transmitter.

[0047] One embodiment of the present disclosure includes a central processor configured to select a transmit beam from a plurality of transmit beams. The central processor may be an integral part of the millimeter-wave module 200. The transmit beam selected by the central processor may be implemented by the transmitter 210. The central processor may also be configured to select a receive beam from a plurality of receive beams. The receive beam selected by the central processor may be implemented by the receiver 212.

[0048] In one or more embodiments, the functions described by the central processor may be implemented in hardware, software, firmware, or any combination thereof. If implemented in software, the functions of the central processor may be stored on or transmitted as one or more instructions or code on a computer-readable medium and executed by a hardware-based processing unit. Computer-readable media may include computer-readable storage media, which correspond to tangible media such as data storage media, or communication media, including any medium that facilitates transfer of a computer program from one place to another, for example, according to a communication protocol. In this manner, computer-readable media may generally correspond to (1) tangible computer-readable storage media that is non-transitory, or (2) a communication medium such as a signal or carrier wave. Data storage media may be any available medium that can be accessed by one or more computers or one or more processors to retrieve instructions, code, and / or data structures for implementing the techniques described in this disclosure. A computer program product may include computer-readable media.

[0049] By way of example, and not limitation, such computer-readable storage media may include RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, flash memory, or any other medium that can be used to store desired program code in the form of instructions or data structures and that can be accessed by a computer. Also, any connection is properly termed a computer-readable medium. For example, if instructions are transmitted from a website, server, or other remote source using coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL), or wireless technologies such as infrared, radio, and microwave, the coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwave are included within the definition of medium. However, it should be understood that computer-readable storage media and data storage media do not include connections, carrier waves, signals, or other transitory media; instead, these storage media are intended to cover non-transitory, tangible storage media. As used herein, disk and disc include compact discs (CDs), laser discs, optical discs, digital versatile discs (DVDs), floppy discs, and Blu-ray discs, where disks typically reproduce data magnetically while discs reproduce data optically with a laser. Combinations of the above should also be included within the scope of computer-readable media.

[0050] The instructions may be executed by one or more processors, such as one or more digital signal processors (DSPs), general-purpose microprocessors, application-specific integrated circuits (ASICs), field-programmable logic arrays (FPGAs), or other equivalent integrated or discrete logic circuitry. Accordingly, the term "processor," as used herein, may refer to any of the foregoing structures, or any other structure suitable for implementing the techniques described herein. Furthermore, in some aspects, the functionality described herein may be provided in dedicated hardware and / or software modules. The techniques may also be implemented entirely in one or more circuits or logic elements.

[0051] The techniques of this disclosure may be implemented in a wide variety of devices or apparatuses, including a wireless handset, an integrated circuit (IC), or a set of ICs (e.g., a chipset). Various components, modules, or units are described in this disclosure to highlight functional aspects of devices configured to perform the techniques of this disclosure, but do not necessarily require realization by various hardware units. Rather, as noted above, the various units may be combined within a hardware unit or may be provided by a collection of interoperating hardware units, including one or more processors as described above, in conjunction with appropriate software and / or firmware.

[0052] In some embodiments, the central processor may be configured to instruct the transmitter processor 230 to transmit multiple signals over multiple channels 250. The central processor may also be configured to instruct the amplifiers 232 and phase shifters 234 to adjust phase delays to generate selected transmit beams at the antenna array 236. The receiver 212 may be instructed to adjust the phase of the multiple phase shifters 244 and multiple LNAs 242 to provide suitable signals received by the receive antenna array 246 to the receiver post-processor 240.

[0053] In some embodiments, the receiver post-processor 240 may digitize multiple signals received on multiple channels 260. The receiver post-processor 240 may further process received signals received from the selected transmit beam via the selected receive beam into first power measurements. The first power measurements may include both a first orthogonal polarization and a second orthogonal polarization. Some orthogonal polarizations may include vertical polarization and horizontal polarization. Other orthogonal polarizations may include left-handed circular polarization (LHCP) and right-handed circular polarization (RHCP). In some embodiments, the power received in the vertical direction may be transmitted to the mobile device as a first orthogonal digital power signal 214. In some embodiments, the power received in the horizontal direction may be transmitted to the mobile device as a second orthogonal digital power signal 216.

[0054] The combination of the central processor in the mobile device and the processor in the millimeter-wave module 200 may change the transmit beam and the receive beam to a second transmit beam of the multiple transmit beams and a second receive beam of the multiple receive beams. The receiver post-processor 240 may receive the second signal. The receiver post-processor 240 may further process the second signal received by the selected receive beam and the selected transmit beam into second power measurements. The second power measurements may include both the first orthogonal polarization and the second orthogonal polarization. The combination of the central processor in the mobile device and the processor in the millimeter-wave module may select a transmit beam and a receive beam and continue to measure the vertical power level and the horizontal power level of the transmit beam pair for each receiver.

[0055] In some embodiments, the processor may form a matrix of transmit and receive beam combinations: Equation 1 denotes elements by TRx beam identification (ID), where the subscript "i" indicates the TRx beam ID number.

[0056] TRx Beam ID:TRx i =(Tx j ,Rx k ) i Equation 1: TRx beam identification for each transmit / receive beam pair

[0057] Equation 1 is a conceptual equation showing the various beam configurations used to designate values ​​measured on receive beams. In the example of Equation 1, the subscript "j" indicates the ID of the transmit beam used during the measurement, and the subscript "k" indicates the ID of the receive beam used during the measurement. In the example of Equation 1, the power measurement taken on TRx beam ID number "i" corresponds to the receive beam with ID "k" configured to receive, while the transmit beam with ID "j" is configured to transmit. The power measured by the receive beam is calculated using the TRx i Taking multiple measurements with multiple receive beams and multiple transmit beams can result in multiple TRx i Values ​​can be obtained. Multiple TRx i The values ​​may be organized into a matrix as shown in Equation 2.

[0058]

number

[0059] In the example of Equation 2, each element of the matrix may have a unique beam ID corresponding to the subscript "i" in Equation 1. In the example of the first element of the matrix in Equation 2, (Tx1, Rx1)1 indicates that the first transmit beam (Tx1) is configured to transmit, while the first receive beam (Rx1) is configured to receive. A transmit / receive beam pair corresponds to a transmit beam configured to transmit and a receive beam configured to receive. The transmit / receive beam pair is designated as beam ID 1.

[0060] Another example is the second element in the second row and first column of the matrix in Equation 2, (Tx2, Rx1) m+1The matrix in Equation 2 is represented by the subscript variable "n" representing several beam ID numbers. The second element indicates that the second transmit beam (Tx2) is configured to transmit and the first receive beam (Rx1) is configured to receive. A transmit / receive beam pair is designated as beam ID m+1. The subscript "m" represents the number of unique receive beam configurations configurable by the hardware and software of the mobile communication device. The matrix in Equation 2 represents several beam ID numbers with the subscript variable "n". "n" represents the number of unique transmit beam configurations configurable by the hardware and software of the mobile communication device.

[0061] In the example of Equation 2, each element of the matrix represents the power measured from a transmit / receive beam pair. In some embodiments, the measured power is the power measured by a particular receive beam when the particular transmit beam was transmitting a signal. In some embodiments, when using receive or transmit beams that are reconfigurable to receive or transmit with two different polarizations per beam configuration, the measured power may include two values. In embodiments where the measured power has two values, a first value may be obtained when both the transmit and receive beams are configured with the same polarization. In the same embodiment, a second value may be obtained when the transmit beam is configured with a polarization orthogonal to the polarization of the receive beam. An example of the first value may be the power measured by the receive beam when the transmit beam transmits with a vertical polarization and the receive beam receives with a vertical polarization. An example of the second value may be the power measured by the receive beam when the transmit beam transmits with a vertical polarization and the receive beam receives with a horizontal polarization.

[0062] In some embodiments, the transmit antenna array and the receive antenna array may be dual-polarized. An antenna array that is dual-polarized means that the antenna array may be reconfigurable to operate between different polarizations. In some embodiments, the antenna array configured to transmit may use both horizontal and vertical polarization during transmission. In some embodiments, the antenna array configured to receive may use both horizontal and vertical polarization during reception. In one embodiment, the transmit antenna array is a dual-polarized antenna array and may thus be able to switch between transmitting a transmit beam with vertical polarization and transmitting a transmit beam with horizontal polarization. In the same embodiment, the receive antenna array is a dual-polarized antenna array and may thus be able to switch between receiving a transmit beam with vertical polarization and receiving a transmit beam with horizontal polarization.

[0063] In some embodiments, four different values ​​may be measured for a given transmit / receive beam pair. In some embodiments, a first value may be the power measured by the receive beam when the transmit beam transmits with vertical polarization and the receive beam receives with vertical polarization. In some embodiments, a second value may be the power measured by the receive beam when the transmit beam transmits with vertical polarization and the receive beam receives with horizontal polarization. In some embodiments, a third value may be the power measured by the receive beam when the transmit beam transmits with horizontal polarization and the receive beam receives with vertical polarization. In some embodiments, a fourth value may be the power measured by the receive beam when the transmit beam transmits with horizontal polarization and the receive beam receives with horizontal polarization.

[0064] In some embodiments, values ​​obtained by measuring different transmit and receive beam polarizations may be combined into two matrices. In some embodiments, a first matrix (e.g., a vertical TRx matrix) may be used to represent values ​​measured using a vertically polarized receive beam across multiple transmit and receive beam pairs. In some embodiments, a second matrix (e.g., a horizontal TRx matrix) may be used to represent values ​​measured using a horizontally polarized receive beam across multiple transmit and receive beam pairs. The vertical TRx matrix and the horizontal TRx matrix may be represented in matrices of a similar format and organization to the matrix in Equation 2.

[0065] In some embodiments, the transmit and receive beams are not generated by dual-polarized antennas and do not have reconfigurable polarization. In some embodiments, when two or more transmit and receive beam pairs are measured, a differential power value may be calculated. In some embodiments, a differential power matrix may be created from the multiple differential power values. The differential power matrix may be defined by Equation 3:

[0066]

number

[0067] Each element in the matrix ΔRx (e.g., Δ j,k ) may be the difference between two power values ​​measured by two transmit / receive beam pairs (e.g., represented by two elements in the matrix TRx). An example element of Equation 3 is Δ 1,1 In Equation 3, the power measurement taken on the transmit / receive beam pair corresponding to TRx beam ID "1" is subtracted from the power measurement taken on the transmit / receive beam pair corresponding to TRx beam ID "1". 2,1 In this example, the power measurement obtained on the transmit / receive beam pair corresponding to TRx beam ID "2" is subtracted from the power measurement obtained on the transmit / receive beam pair corresponding to TRx beam ID "1."

[0068] In some embodiments, the transmit and receive beams may be generated by a dual-polarized antenna configured to switch between different polarizations. In embodiments where the transmit and receive beams are received using a dual-polarized antenna and reconfigurable polarizations, the differential power value may include two values, which are expressed as Δ x,y It can be expressed as:

[0069] Δ x,y =(((Tx j ,Rx k ) x -(Tx j ,Rx k ) y ) V ,((Tx j ,Rx k ) x -(Tx j ,Rx k ) y ) H ) Equation 4: Differential (Rx) power matrix with orthogonal polarization

[0070] In the example of Equation 4, Δ x,y represents two values: a differential power value in a vertical orientation and a differential power value in a horizontal polarization. The first transmit / receive beam pair with TRx beam ID "x" is separated into a vertical component (e.g., "V") and a horizontal component (e.g., "H"). Similarly, the second transmit / receive beam pair with TRx beam ID "y" is separated into a vertical component (e.g., "V") and a horizontal component (e.g., "H"). Once the two measurement pairs are separated into their respective polarizations, a difference can be calculated between each polarization. The difference can be calculated by subtracting the vertical component of TRx beam ID "y" from the vertical component of TRx beam ID "x" and subtracting the horizontal component of TRx beam ID "y" from the horizontal component of TRx beam ID "x". In some embodiments, further calculations can be performed on the differential pair. In one embodiment, a simple sum of the vertical and horizontal polarizations can be calculated to obtain a single value from the two polarization values ​​representing the differential power value. In one embodiment, an absolute value, or vector magnitude, calculation may be performed to obtain a single value from the two polarization values ​​representing the differential power value.

[0071] A conceptual graphical representation of the differential power matrix may be plotted versus the TRx beam ID. The differential power matrix may be determined in various environments, which may include placing various objects near the mobile communication device and plotting received power across various TRx beam IDs.

[0072] FIG. 5 is a conceptual graph illustrating an example of a differential power matrix plotted for multiple TRx beam IDs in various environments, in accordance with one or more techniques of the present disclosure. The plot in FIG. 5 is a line graph plotted on a graph with a single horizontal axis and a single vertical axis. The horizontal axis represents pair permutations of transmit and receive beam pairs. The permutations may be represented using the corresponding TRx beam IDs. The vertical axis represents differential power between permuted pairs. In some embodiments, the differential power between permuted pairs represents differential power values ​​calculated with Equation 3. In some embodiments, the differential power between permuted pairs represents differential power values ​​calculated with Equation 4. The graph in FIG. 5 represents a plot of differential power values ​​calculated across multiple permutations and in multiple environments.

[0073] In the example of FIG. 5 , multiple environments were calculated to demonstrate how a particular transmit / receive beam pair among the multiple transmit / receive beam pairs can be used to indicate the presence of biological tissue. The plot corresponding to biological tissue 528 represents differential power measurements obtained across the multiple transmit / receive beam pairs. The graph of FIG. 5 shows a plot corresponding to a second environment 526, a plot corresponding to a third environment 524, a plot corresponding to a fourth environment 522, and a plot corresponding to a fifth environment 520. In the example of FIG. 5 , the fourth environment may be free space. Free space may refer to an environment in which a mobile communication device is located where there are a limited number of materials that cause reflection of energy from the transmit beam. An example of free space may be an anechoic chamber. The fifth environment 520 may be metal. Metal has high electrical conductivity and may cause significant reflection of electromagnetic energy. In some examples of FIG. 5 , in a first unique multiple transmit / receive beam pairs, metal may have a higher differential power value 530 than other environments. In some examples of FIG. 5 , metal may have a lower differential power value than biological tissue. In some embodiments, in the second unique plurality of transmit and receive beam pairs, biological tissue (eg, a human hand) may have a higher differential power value 532 than other environments.

[0074] In the example of FIG. 5 , the differential power between permuted pairs of transmit and receive beam pairs plotted against pair permutations of the transmit and receive beam pairs can indicate which pair of transmit and receive beam pairs should be used to detect biological tissue. For a central processor of a mobile communication device, processing the differential power between beam pairs can be data-intensive and time-limited. In some examples, calculating the differential power between all permuted pairs can be a time-limited process, while calculating the difference between a limited number of pairs can be an open-ended process. Determining which specific beam pairs of a limited number of beam pairs should be used to compare beam pairs on a mobile communication device limits processing resources while improving detection accuracy.

[0075] In the example of FIG. 5 , pairs to be used in comparing transmit beam pairs to determine whether biological tissue is in proximity to the antenna array can be selected from among the transmit and receive beam pairs. Measuring and plotting the differential power for multiple transmit and receive beam pairs across various materials indicates which transmit and receive beam pairs should be used in comparing transmit and receive beam pairs according to the techniques of the present disclosure. In some examples, for a first unique plurality of transmit and receive beam pairs, metal may have a higher differential power value 530 than other environments. The first unique plurality of transmit and receive beam pairs may correspond to a specific transmit and receive beam pair that cannot be used in comparing beam pairs according to the techniques of the present disclosure. In some examples, for a second unique plurality of transmit and receive beam pairs, biological tissue (e.g., a human hand) may have a higher differential power value 532 than other environments. The second unique plurality of pairs may be used in comparing beam pairs according to the techniques of the present disclosure.

[0076] In the example of FIG. 5 , the comparison between transmit and receive beam pairs may be performed using multiple transmit and receive beam pairs that most significantly respond to the presence of biological tissue (e.g., a human hand). These transmit and receive beam pairs may be designated as compare pairs. The calculated differential power of the compare pairs may be further compared to a threshold value to determine whether biological tissue is present. The threshold value may be a value determined through measurement, testing, or calibration. The threshold value may correspond to a power level, and a differential power value of the compare pair exceeding the threshold value indicates a highly reliable indication that a human hand is in proximity to the mobile device. In some examples, a change in the differential power value obtained for the compare pair when a different object is present may correspond to the presence of biological tissue (e.g., a human hand). In some examples, the change in differential power from a value when no object is present to a value when biological tissue is in proximity to the antenna may be compared to a threshold value. In some examples, the change in power between a first differential power measurement at a first time point and a second differential power measurement at a second time point may be compared to a threshold value.

[0077] In some examples, when a differential power measurement of a compare pair is taken at a first time point and a second differential power measurement of the compare pair is taken at a second time point, the power change may be compared to a threshold value, and if the power change exceeds the threshold value, the central processor may determine that a significant and reliable indication of proximity of biological tissue to the mobile communications device has been presented.

[0078] FIG. 6 is a conceptual flowchart illustrating an example method for detecting biological tissue proximate to an antenna array of a mobile communication device, in accordance with one or more techniques of the present disclosure. In some examples of FIG. 6, the mobile communication device is configured to transmit (610) various transmit beams. Some examples of these beams are shown as transmit beam 104 in FIG. 1. In some examples, the transmit beams may be generated by antenna arrays 310, 320, and 330 of FIGS. 3A, 3B, and 3C, respectively. In some examples, the transmit beams transmit electromagnetic energy that, after interacting with surrounding matter, is reflected toward the receive antenna array. In some examples, the transmit beams may have reconfigurable polarization. The reconfigurable polarization may include orthogonal polarizations, some examples of which include vertical and horizontal polarizations, and RHCP and LHCP.

[0079] In some embodiments, the mobile communications device may be configured to receive various receive beams, each of which is paired with a transmit beam from various transmit beams (612). In some embodiments, the antenna array 106 may be configured as a receive array by electromagnetically coupling antenna elements in the antenna array 106 to one or more RF receivers. In some embodiments, the receive beams may be generated by the antenna arrays 310, 320, and 330 of FIGS. 3A, 3B, and 3C, respectively. In some embodiments, the receive beams may be configured to receive electromagnetic energy on a given channel at the same time that the transmit beams are transmitting. In some embodiments, the receive beams may have reconfigurable polarizations. The reconfigurable polarizations may include orthogonal polarizations, some examples of which include vertical and horizontal polarizations, and RHCP and LHCP.

[0080] In the example of FIG. 6, the mobile communication device may determine one or more transmit parameters in response to determining that biological tissue is present near the antenna of the wireless communication device (614). In some examples, the mobile communication device may determine that biological tissue is present near the antenna of the wireless communication device by comparing received power measured by a receive beam to a threshold. In some examples, received power measured by a first receive beam may be compared to received power measured by a second receive beam and compared to a threshold. In some examples, received power measured by a receive beam in the presence of a first transmitter may be compared to received power measured by a receive beam in the presence of a second transmitter. In some examples, any combination of receive beam measurements may be made using different orthogonal beam polarizations. In some examples, power measured by a receive beam at a first time point may be compared to power measured by a receive beam at a second time point and compared to a threshold. Upon determining that biological tissue is present near the antenna of the wireless communication device, the wireless communication device may respond.

[0081] In the example of FIG. 6, the mobile communication device may determine 614 one or more transmit parameters in response to determining that biological tissue is present near the antenna of the wireless communication device. Some parameters may include a gain or power level of the power amplifier 232 of FIG. 2, a delay value in the phase shifter 234 of FIG. 2, or a modulation technique implemented by the transmitter processor 230 of FIG. 2. In some examples, determining the transmit parameters may include determining a communication message to transmit to a wireless communication system indicating the presence of an obstacle in the channel. The wireless communication system may include a base station, and the mobile communication device may include a cellular phone. In some examples, the transmit parameters may correspond to selecting a different communication module. In some examples, the transmit parameters may be the ID of a different communication module to be selected for use in a next transmission. Selecting a different communication module may include switching the RF radio to one that increases the amount of power received by the receiver while reducing the amount of electromagnetic energy lost to obstructing biological tissue. In some examples, the transmit parameters correspond to the angular positions of a main lobe and a side lobe of the transmit beam 104. In some embodiments, the angular position may include a phase delay value implemented by phase shifter 234 of FIG. 2. Steering the main lobe or side lobes of the transmit beam 104 may be performed by varying the phase and amplitude of replica signals between electromagnetically connected antenna elements. For example, by varying the phase between horizontally adjacent elements, the main beam may be steered horizontally along the azimuth direction. Similarly, by varying the phase between vertically adjacent elements, the main beam may be steered vertically along the elevation direction. In some embodiments, the phase shift and gain changes may be performed by the transceiver.

[0082] In the example of FIG. 6, the mobile communication device may transmit (616) a signal using one or more transmit parameters. In some examples, the signal transmitted by the mobile communication device may be transmitted wirelessly using the transmit antenna array 102 forming a transmit beam 104 for transmitting the signal 116 of FIG. 1. In some examples, the mobile communication device may be a cellular phone communicating with a base station, and the signal indicates the presence of an object or material obstruction in the communication channel. In some examples, the object or material obstruction may be living tissue or a material having the electromagnetic properties of living tissue. In some cases, the signal may be a response to a wireless communication system, such as a base station, indicating that the mobile communication device is switching to a different communication module. In some examples, the signal may indicate the received power the mobile communication device is measuring from the wireless communication system. In some examples, the signal may indicate which comparison pair the mobile communication device is using to compare differential power received by multiple transmit / receive beam pairs.

[0083] In some embodiments, a mobile communication device outputs a power level high enough to affect the length of battery operation time from a given charge. When a mobile communication device is in close proximity to a user, the user's body absorbs electromagnetic energy from the transmit beam, degrading the signal received by the receiver. In response to the signal degradation, the transmitter power level increases, accelerating the rate at which battery operation time decreases. In some embodiments, the proximity of human tissue to an antenna, i.e., an antenna array, can cause significant losses in the wireless communication channel. In some embodiments, significant losses in the wireless communication channel can cause the mobile communication device to compensate by increasing the amount of transmit power, thereby shortening the battery's operation time before it needs to be recharged.

[0084] It may be desirable for a mobile communication device to determine whether biological tissue is in close proximity to the mobile communication device. For example, the absorptivity and reflectivity of human tissue can degrade communication channel quality between a mobile communication device and a base station. Furthermore, various regulations set specific absorption rate (SAR) standards for cellular communication devices due to biological tissue. Determining that biological tissue is juxtaposed with a communication device may facilitate some control of antenna gain toward a base station, taking into account the location of the biological tissue. Reducing transmitter power while maintaining channel quality extends battery operating time between charges.

[0085] According to one or more techniques of the present disclosure, a mobile communication device may determine whether a human hand is present near the device using an RF transmitter electromagnetically coupled to a transmit antenna system and an RF receiver electromagnetically coupled to a receive antenna system. The mobile communication device may transmit on multiple transmit beams using the transmit antenna system and receive on multiple receive beams using the receive antenna system. In some embodiments, each transmit beam of the multiple transmit beams may be paired with a receive beam of the multiple receive beams. In some embodiments, a received power received by a first multiple transmit / receive beam pair may be compared to a received power received by a second multiple transmit / receive beam pair. The comparison may include a difference calculation, which may calculate multiple differential power measurements across permutations of the transmit / receive beam pairs. In some embodiments, the difference value may be compared to one or more predetermined thresholds to determine whether biological tissue is in proximity to the antenna array of the mobile communication device. In some embodiments, upon determining that biological tissue is in proximity to the antenna array of the mobile communication device, the mobile communication device may determine multiple transmit parameters. In some embodiments, the transmit parameters may include other parameters related to improving transmitter efficiency while maintaining the quality of the signal received by the receiver. In some embodiments, the mobile communications device may transmit a signal indicating the values ​​of one or more of the transmission parameters.

[0086] The following numbered examples may illustrate one or more aspects of the present disclosure. Example 1. A method comprising: transmitting a plurality of transmit beams via a first antenna array of a mobile communication device; and receiving a plurality of receive beams via a second antenna array of the mobile communication device, each of a plurality of beam pairs comprising a respective transmit beam of the plurality of transmit beams and a respective receive beam of the plurality of receive beams, the method further comprising: determining whether biological tissue is in proximity to the mobile communication device based on a comparison between beam pairs of the plurality of beam pairs; determining one or more transmit parameters in response to determining that the biological tissue is in proximity to the mobile communication device; and transmitting a signal using the one or more transmit parameters.

[0087] Example 2. The method of example 1, wherein the plurality of transmit beams are generated from a plurality of transceivers electrically connected to dual-polarized antenna elements in the first antenna array.

[0088] Example 3. The method of example 1, wherein the plurality of receive beams are received by a plurality of transceivers electrically connected to dual-polarized antenna elements in the second antenna array.

[0089] Example 4. The method of example 1, wherein the first antenna array and the second antenna array are comprised within a single antenna array.

[0090] Example 5. The method described in Example 1, wherein determining whether the biological tissue is in proximity to the mobile communication device includes identifying a respective power level of a plurality of power levels for each beam pair of the plurality of beam pairs, the respective power levels representing the amount of power of a received beam of the respective beam pair while a transmitted beam of the respective beam pair is transmitted, and the determining further includes determining whether the biological tissue is in proximity to the mobile communication device based on a difference between a first received power level of the plurality of power levels and a second received power level of the plurality of received power levels.

[0091] Example 6. The method described in Example 5, wherein determining whether the biological tissue is in proximity to the mobile communication device based on the difference between the first received power level and the second received power level includes determining that the biological tissue is in proximity to the mobile communication device in response to determining that the difference exceeds a threshold.

[0092] Example 7. The method of example 1, wherein the multiple transmit beams include multiple modified copies of the same signal.

[0093] Example 8. The method of Example 1, wherein the first antenna array is included in a current communication module of a plurality of communication modules of the mobile communication device, and determining the one or more transmission parameters includes one or more of determining a transmission power and selecting a different communication module of the plurality of communication modules.

[0094] Example 9. The method of example 1, further comprising, in response to determining that the biological tissue is in proximity to the mobile communication device, wirelessly communicating a message to a base station indicating the presence of an obstacle.

[0095] Example 10. A mobile communication device comprising: a first antenna array configured to transmit a plurality of transmit beams; and a second antenna array configured to receive a plurality of receive beams, each of the plurality of beam pairs including a respective transmit beam of the plurality of transmit beams and a respective receive beam of the plurality of receive beams; the mobile communication device further comprising: one or more processors configured to determine whether an object is in proximity to the mobile communication device based on a comparison between beam pairs among the plurality of beam pairs; and a radio configured to determine one or more transmit parameters and transmit a signal using the one or more transmit parameters when it is determined that an object is in proximity to the mobile communication device.

[0096] Example 11. A mobile communication device as described in Example 10, wherein the first antenna array comprises a plurality of transceivers electrically connected to dual-polarized antenna elements.

[0097] Example 12. A mobile communication device as described in Example 10, wherein the second antenna array comprises a plurality of transceivers electrically connected to dual-polarized antenna elements.

[0098] Example 13. The mobile communication device of Example 10, wherein the first antenna array and the second antenna array are included within a single antenna array.

[0099] Example 14. A mobile communication device as described in Example 10, wherein, to determine whether the biological tissue is in proximity to the mobile communication device, the one or more processors are configured to identify, for each beam pair of the plurality of beam pairs, a respective power level of a plurality of power levels, the respective power level representing the amount of power of a received beam of the respective beam pair while a transmitted beam of the respective beam pair is transmitted, and the one or more processors are further configured to determine whether the biological tissue is in proximity to the mobile communication device based on a difference between a first received power level of the plurality of power levels and a second received power level of the plurality of received power levels.

[0100] Example 15. A mobile communication device as described in Example 14, wherein, in order to determine whether the biological tissue is in proximity to the mobile communication device based on the difference between the first received power level and the second received power level, the one or more processors are configured to determine that the biological tissue is in proximity to the mobile communication device in response to determining that the difference exceeds a threshold.

[0101] Example 16. The mobile communications device of Example 10, wherein the one or more processors are configured to modify copies of the same signal to generate multiple transmit beams.

[0102] Example 17. A mobile communication device as described in Example 10, wherein the first antenna array is included in a current communication module among a plurality of communication modules of the mobile communication device, and in order to determine the one or more transmission parameters, the one or more processors are configured to perform the following: determining a transmission power; and selecting a different communication module among the plurality of communication modules.

[0103] Example 18. A mobile communication device as described in Example 10, wherein, in response to determining that the biological tissue is in proximity to the mobile communication device, the one or more processors are configured to communicate a message to a base station indicating the presence of an obstacle.

[0104] Example 19. A mobile communication device as described in Example 15, wherein the one or more processors are configured to compare a power change between a first received power level at a first time point and a second received power level at a second time point with the threshold value to calculate the power change.

[0105] Example 20. A mobile communication device as described in Example 15, wherein, to measure received power levels, the one or more processors are configured to measure vertical power levels and horizontal power levels of each transmit / receive beam pair.

[0106] Various embodiments of the present disclosure have been described. Any combination of the described systems, operations, or functions is contemplated. These and other embodiments are intended to be within the scope of the following claims.

Claims

1. 1. A method comprising: transmitting a plurality of transmit beams via a first antenna array of the mobile communication device; receiving a plurality of receive beams via a second antenna array of the mobile communication device, each of a plurality of beam pairs including a respective transmit beam of the plurality of transmit beams and a respective receive beam of the plurality of receive beams, the method further comprising: determining whether biological tissue is in proximity to the mobile communication device based on a comparison between beam pairs of the plurality of beam pairs; determining one or more transmission parameters in response to determining proximity of the biological tissue to the mobile communication device; transmitting a signal using the one or more transmission parameters; A method comprising:

2. The method of claim 1 , wherein the plurality of transmit beams are generated from a plurality of transceivers electrically connected to dual-polarized antenna elements in the first antenna array.

3. The method of claim 1 , wherein the plurality of receive beams are received by a plurality of transceivers electrically connected to dual-polarized antenna elements in the second antenna array.

4. The method of any one of claims 1 to 3, wherein the first antenna array and the second antenna array are comprised within a single antenna array.

5. Determining whether the biological tissue is in proximity to the mobile communication device includes: and identifying a respective power level of a plurality of power levels for each beam pair of the plurality of beam pairs, the respective power level representing an amount of power in a receive beam of the respective beam pair while a transmit beam of the respective beam pair is being transmitted, the determining further comprising: determining whether the biological tissue is in proximity to the mobile communication device based on a difference between a first received power level of the plurality of power levels and a second received power level of the plurality of received power levels; The method according to any one of claims 1 to 4, comprising:

6. Determining whether the biological tissue is in proximity to the mobile communication device based on the difference between the first received power level and the second received power level includes: determining that the biological tissue is in proximity to the mobile communication device in response to determining that the difference exceeds a threshold; The method of claim 5 , comprising:

7. The method of any one of claims 1 to 6, wherein the multiple transmit beams comprise multiple modified copies of the same signal.

8. the first antenna array is included in a current communication module of a plurality of communication modules of the mobile communication device, and determining the one or more transmission parameters includes: determining a transmit power; selecting a different communication module from the plurality of communication modules; The method of any one of claims 1 to 7, comprising one or more of:

9. in response to determining that the biological tissue is in proximity to the mobile communications device, wirelessly communicating a message to a base station indicating the presence of an obstruction; The method of any one of claims 1 to 8, further comprising:

10. 1. A mobile communication device, comprising: a first antenna array configured to transmit a plurality of transmit beams; and a second antenna array configured to receive a plurality of receive beams, each of a plurality of beam pairs including a respective transmit beam of the plurality of transmit beams and a respective receive beam of the plurality of receive beams, wherein the mobile communication device further comprises: one or more processors configured to determine whether an object is in proximity to the mobile communication device based on a comparison between beam pairs of the plurality of beam pairs; a radio configured to determine one or more transmission parameters and transmit a signal using the one or more transmission parameters upon determining that an object is in proximity to the mobile communication device; A mobile communication device comprising:

11. The mobile communication device of claim 10 , wherein the first antenna array comprises a plurality of transceivers electrically connected to dual-polarized antenna elements.

12. The mobile communication device of claim 10 , wherein the second antenna array comprises a plurality of transceivers electrically connected to dual-polarized antenna elements.

13. A mobile communication device according to any one of claims 10 to 12, wherein the first antenna array and the second antenna array are comprised within a single antenna array.

14. To determine whether the biological tissue is in proximity to the mobile communication device, the one or more processors: and configured to identify, for each beam pair of the plurality of beam pairs, a respective power level of a plurality of power levels, the respective power level representing an amount of power in a receive beam of the respective beam pair while a transmit beam of the respective beam pair is being transmitted, and the one or more processors further: and determining whether the biological tissue is in proximity to the mobile communication device based on a difference between a first received power level of the plurality of power levels and a second received power level of the plurality of received power levels. A mobile communication device according to any one of claims 10 to 13.

15. To determine whether the biological tissue is in proximity to the mobile communication device based on the difference between the first received power level and the second received power level, the one or more processors: In response to determining that the difference exceeds a threshold, determining that the biological tissue is in proximity to the mobile communication device; The mobile communication device of claim 14 configured to:

16. 16. A mobile communication device according to any one of claims 10 to 15, wherein the one or more processors are configured to modify copies of the same signal to generate multiple transmit beams.

17. the first antenna array is included in a current communication module of a plurality of communication modules of the mobile communication device, and to determine the one or more transmission parameters, the one or more processors: determining a transmit power; selecting a different communication module from the plurality of communication modules; A mobile communication device according to any one of claims 10 to 16, configured to execute:

18. 18. The mobile communication device of claim 10, wherein, in response to determining that the biological tissue is in proximity to the mobile communication device, the one or more processors are configured to communicate a message to a base station indicating the presence of an obstacle.

19. 16. The mobile communication device of claim 15, wherein the one or more processors are configured to calculate a power change between a first received power level at a first time point and a second received power level at a second time point by comparing the power change to the threshold.

20. 16. The mobile communication device of claim 15, wherein to measure received power levels, the one or more processors are configured to measure vertical and horizontal power levels of each transmit and receive beam pair.

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