Security enhancements with a reconfigurable intelligent surface

Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may receive a first signal associated with a downlink control channel, wherein the first signal uses a modulation signature that identifies a first security key associated with a reconfigurable intelligent surface (RIS), and wherein the first signal includes a second security key. The UE may receive a second signal associated with a downlink shared channel, wherein the second signal includes a third security key, and wherein the second signal is authenticated by the UE based at least in part on the first security key, the second security key, and the third security key. Numerous other aspects are described.

FIELD OF THE DISCLOSURE

Aspects of the present disclosure generally relate to wireless communication and to techniques and apparatuses for security enhancements with a reconfigurable intelligent surface (RIS).

BACKGROUND

SUMMARY

Some aspects described herein relate to a method of wireless communication performed by a user equipment (UE). The method may include receiving a first signal associated with a downlink control channel, wherein the first signal uses a modulation signature that identifies a first security key associated with a reconfigurable intelligent surface (RIS), and wherein the first signal includes a second security key. The method may include receiving a second signal associated with a downlink shared channel, wherein the second signal includes a third security key, and wherein the second signal is authenticated by the UE based at least in part on the first security key, the second security key, and the third security key.

Some aspects described herein relate to a method of wireless communication performed by a base station. The method may include transmitting, to an RIS, an indication of a first security key associated with the RIS, wherein the first security key is to be added, using a modulation signature, to signals reflected by the RIS. The method may include transmitting a first signal that is associated with a downlink control channel, wherein the first signal includes a second security key, and wherein the first signal is to be reflected by the RIS. The method may include transmitting a second signal that is associated with a downlink shared channel, wherein the second signal includes a third security key, and wherein the first security key, the second security key, and the third security key enable a UE to authenticate the second signal.

Some aspects described herein relate to a method of wireless communication performed by an RIS. The method may include receiving, from a base station, an indication of a first security key associated with the RIS, wherein the first security key is to be added, using a modulation signature, to signals reflected by the RIS. The method may include receiving, from the base station, a first signal associated with a downlink control channel, wherein the first signal includes a second security key. The method may include redirecting, to a UE, the first signal by including the modulation signature that identifies the first security key in the first signal. The method may include redirecting, to the UE, a second signal, wherein the second signal includes a third security key, and wherein the first security key, the second security key, and the third security key enable the UE to authenticate the second signal.

Some aspects described herein relate to a UE for wireless communication. The user equipment may include a memory and one or more processors coupled to the memory. The one or more processors may be configured to receive a first signal associated with a downlink control channel, wherein the first signal uses a modulation signature that identifies a first security key associated with an RIS, and wherein the first signal includes a second security key. The one or more processors may be configured to receive a second signal associated with a downlink shared channel, wherein the second signal includes a third security key, and wherein the second signal is authenticated by the UE based at least in part on the first security key, the second security key, and the third security key.

Some aspects described herein relate to a base station for wireless communication. The base station may include a memory and one or more processors coupled to the memory. The one or more processors may be configured to transmit, to an RIS, an indication of a first security key associated with the RIS, wherein the first security key is to be added, using a modulation signature, to signals reflected by the RIS. The one or more processors may be configured to transmit a first signal that is associated with a downlink control channel, wherein the first signal includes a second security key, and wherein the first signal is to be reflected by the RIS. The one or more processors may be configured to transmit a second signal that is associated with a downlink shared channel, wherein the second signal includes a third security key, and wherein the first security key, the second security key, and the third security key enable a UE to authenticate the second signal.

Some aspects described herein relate to an RIS for wireless communication. The reconfigurable intelligent surface may include a memory and one or more processors coupled to the memory. The one or more processors may be configured to receive, from a base station, an indication of a first security key associated with the RIS, wherein the first security key is to be added, using a modulation signature, to signals reflected by the RIS. The one or more processors may be configured to receive, from the base station, a first signal associated with a downlink control channel, wherein the first signal includes a second security key. The one or more processors may be configured to redirect, to a UE, the first signal by including the modulation signature that identifies the first security key in the first signal. The one or more processors may be configured to redirect, to the UE, a second signal, wherein the second signal includes a third security key, and wherein the first security key, the second security key, and the third security key enable the UE to authenticate the second signal.

Some aspects described herein relate to a non-transitory computer-readable medium that stores a set of instructions for wireless communication by a UE. The set of instructions, when executed by one or more processors of the UE, may cause the UE to receive a first signal associated with a downlink control channel, wherein the first signal uses a modulation signature that identifies a first security key associated with an RIS, and wherein the first signal includes a second security key. The set of instructions, when executed by one or more processors of the UE, may cause the UE to receive a second signal associated with a downlink shared channel, wherein the second signal includes a third security key, and wherein the second signal is authenticated by the UE based at least in part on the first security key, the second security key, and the third security key.

Some aspects described herein relate to a non-transitory computer-readable medium that stores a set of instructions for wireless communication by a base station. The set of instructions, when executed by one or more processors of the base station, may cause the base station to transmit, to an RIS, an indication of a first security key associated with the RIS, wherein the first security key is to be added, using a modulation signature, to signals reflected by the RIS. The set of instructions, when executed by one or more processors of the base station, may cause the base station to transmit a first signal that is associated with a downlink control channel, wherein the first signal includes a second security key, and wherein the first signal is to be reflected by the RIS. The set of instructions, when executed by one or more processors of the base station, may cause the base station to transmit a second signal that is associated with a downlink shared channel, wherein the second signal includes a third security key, and wherein the first security key, the second security key, and the third security key enable a UE to authenticate the second signal.

Some aspects described herein relate to a non-transitory computer-readable medium that stores a set of instructions for wireless communication by an RIS. The set of instructions, when executed by one or more processors of the RIS, may cause the RIS to receive, from a base station, an indication of a first security key associated with the RIS, wherein the first security key is to be added, using a modulation signature, to signals reflected by the RIS. The set of instructions, when executed by one or more processors of the RIS, may cause the RIS to receive, from the base station, a first signal associated with a downlink control channel, wherein the first signal includes a second security key. The set of instructions, when executed by one or more processors of the RIS, may cause the RIS to redirect, to a UE, the first signal by including the modulation signature that identifies the first security key in the first signal. The set of instructions, when executed by one or more processors of the RIS, may cause the RIS to redirect, to the UE, a second signal, wherein the second signal includes a third security key, and wherein the first security key, the second security key, and the third security key enable the UE to authenticate the second signal.

Some aspects described herein relate to an apparatus for wireless communication. The apparatus may include means for receiving a first signal associated with a downlink control channel, wherein the first signal uses a modulation signature that identifies a first security key associated with an RIS, and wherein the first signal includes a second security key. The apparatus may include means for receiving a second signal associated with a downlink shared channel, wherein the second signal includes a third security key, and wherein the second signal is authenticated by the apparatus based at least in part on the first security key, the second security key, and the third security key.

Some aspects described herein relate to an apparatus for wireless communication. The apparatus may include means for transmitting, to an RIS, an indication of a first security key associated with the RIS, wherein the first security key is to be added, using a modulation signature, to signals reflected by the RIS. The apparatus may include means for transmitting a first signal that is associated with a downlink control channel, wherein the first signal includes a second security key, and wherein the first signal is to be reflected by the RIS. The apparatus may include means for transmitting a second signal that is associated with a downlink shared channel, wherein the second signal includes a third security key, and wherein the first security key, the second security key, and the third security key enable a UE to authenticate the second signal.

Some aspects described herein relate to an apparatus for wireless communication. The apparatus may include means for receiving, from a base station, an indication of a first security key associated with the apparatus, wherein the first security key is to be added, using a modulation signature, to signals reflected by the apparatus. The apparatus may include means for receiving, from the base station, a first signal associated with a downlink control channel, wherein the first signal includes a second security key. The apparatus may include means for redirecting, to a UE, the first signal by including the modulation signature that identifies the first security key in the first signal. The apparatus may include means for redirecting, to the UE, a second signal, wherein the second signal includes a third security key, and wherein the first security key, the second security key, and the third security key enable the UE to authenticate the second signal.

DETAILED DESCRIPTION

In some aspects, the UE120may include a communication manager140. As described in more detail elsewhere herein, the communication manager140may receive a first signal associated with a downlink control channel, wherein the first signal uses a modulation signature that identifies a first security key associated with a reconfigurable intelligent surface (RIS)160, and wherein the first signal includes a second security key; and receive a second signal associated with a downlink shared channel, wherein the second signal includes a third security key, and wherein the second signal is authenticated by the UE based at least in part on the first security key, the second security key, and the third security key. Additionally, or alternatively, the communication manager140may perform one or more other operations described herein.

In some aspects, the base station110may include a communication manager150. As described in more detail elsewhere herein, the communication manager150may transmit, to the RIS160, an indication of a first security key associated with the RIS, wherein the first security key is to be added, using a modulation signature, to signals reflected by the RIS; transmit a first signal that is associated with a downlink control channel, wherein the first signal includes a second security key, and wherein the first signal is to be reflected by the RIS; and transmit a second signal that is associated with a downlink shared channel, wherein the second signal includes a third security key, and wherein the first security key, the second security key, and the third security key enable a UE120to authenticate the second signal. Additionally, or alternatively, the communication manager150may perform one or more other operations described herein.

As shown inFIG.1, the wireless network100may include an RIS160. The RIS160may include one or more reconfigurable elements capable of redirecting or reflecting signals transmitted by a base station110or a UE120. In some aspects, the RIS160may include a communication manager170. As described in more detail elsewhere herein, the communication manager170may receive, from a base station, an indication of a first security key associated with the RIS, wherein the first security key is to be added, using a modulation signature, to signals reflected by the RIS; receive, from the base station, a first signal associated with a downlink control channel, wherein the first signal includes a second security key; redirect, to a UE120, the first signal by including the modulation signature that identifies the first security key in the first signal; and redirect, to the UE, a second signal, wherein the second signal includes a third security key, and wherein the first security key, the second security key, and the third security key enable the UE to authenticate the second signal. Additionally, or alternatively, the communication manager170may perform one or more other operations described herein.

In some aspects, the UE120includes means for receiving a first signal associated with a downlink control channel, wherein the first signal uses a modulation signature that identifies a first security key associated with an RIS, and wherein the first signal includes a second security key; and/or means for receiving a second signal associated with a downlink shared channel, wherein the second signal includes a third security key, and wherein the second signal is authenticated by the UE based at least in part on the first security key, the second security key, and the third security key. The means for the UE120to perform operations described herein may include, for example, one or more of communication manager140, antenna252, modem254, MIMO detector256, receive processor258, transmit processor264, TX MIMO processor266, controller/processor280, or memory282.

In some aspects, the base station110includes means for transmitting, to an RIS, an indication of a first security key associated with the RIS, wherein the first security key is to be added, using a modulation signature, to signals reflected by the RIS; means for transmitting a first signal that is associated with a downlink control channel, wherein the first signal includes a second security key, and wherein the first signal is to be reflected by the RIS; and/or means for transmitting a second signal that is associated with a downlink shared channel, wherein the second signal includes a third security key, and wherein the first security key, the second security key, and the third security key enable a UE to authenticate the second signal. The means for the base station110to perform operations described herein may include, for example, one or more of communication manager150, transmit processor220, TX MIMO processor230, modem232, antenna234, MIMO detector236, receive processor238, controller/processor240, memory242, or scheduler246.

In some aspects, the RIS160includes means for receiving, from a base station, an indication of a first security key associated with the RIS, wherein the first security key is to be added, using a modulation signature, to signals reflected by the RIS; means for receiving, from the base station, a first signal associated with a downlink control channel, wherein the first signal includes a second security key; means for redirecting, to a UE, the first signal by including the modulation signature that identifies the first security key in the first signal; and/or means for redirecting, to the UE, a second signal, wherein the second signal includes a third security key, and wherein the first security key, the second security key, and the third security key enable the UE to authenticate the second signal. In some aspects, the means for the RIS160to perform operations described herein may include, for example, one or more of communication manager170, a transmit processor, a TX MIMO processor, a modem, an antenna, a MIMO detector, a receive processor, a controller/processor, and/or a memory.

FIG.3is a diagram illustrating an example300of communications using an RIS, in accordance with the present disclosure. As shown inFIG.3, a base station110may communicate with a UE120in a wireless network, such as the wireless network100. The base station110and the UE120may use an RIS305to communicate with one another. For example, the RIS305may reflect or redirect a signal to the base station110and/or the UE120. The RIS305may also be referred to as an intelligent reflecting surface. In some examples, the RIS305may be a repeater.

The RIS305may be, or may include, a planar or two-dimensional structure or surface that is designed to have properties to enable a dynamic control of signals or electromagnetic waves reflected and/or redirected by the RIS305. The RIS305may include one or more reconfigurable elements. For example, the RIS305may include an array of reconfigurable elements (e.g., an array of uniformly distributed reconfigurable elements). The reconfigurable elements may be elements with a reconfigurable electromagnetic characteristic. For example, the electromagnetic characteristic may include a reflection characteristic (e.g., a reflection coefficient), a scattering characteristic, an absorption characteristic, and/or a diffraction characteristic. The electromagnetic characteristic(s) of each reconfigurable element may be independently controlled and changed over time. The electromagnetic characteristic(s) of each reconfigurable element may be independently configured such that the combination of configured states of the reconfigurable elements reflects an incident signal or waveform in a controlled manner. For example, the reconfigurable elements may be configured to reflect or redirect an impinging signal in a controlled manner, such as by reflecting the impinging signal in a desired direction, with a desired beam width, with a desired phase, with a desired amplitude, and/or with a desired polarization, among other examples. In other words, the RIS305may be capable of modifying one or more properties (e.g., direction, beam width, phase, amplitude, and/or polarization) of an impinging signal.

The reconfigurable elements of the RIS305may be controlled and/or configured by an RIS controller310. The RIS controller310may be a control module (e.g., a controller and/or a processor) that is capable of configuring the electromagnetic characteristic(s) of each reconfigurable element of the RIS305. The RIS controller310may be, or may be included in, the communication manager170. Alternatively, the communication manager170may be included in the RIS controller310. The RIS controller310may receive control communications (e.g., from a base station110and/or a UE120) indicating one or more properties of reflected signals (e.g., indicating a desired direction, a desired beam width, a desired phase, a desired amplitude, and/or a desired polarization). Therefore, in some examples, the RIS305may be capable of receiving communications (e.g., via the RIS305and/or the RIS controller310). In some examples, the RIS305and/or the RIS controller310may not have transmit capabilities (e.g., the RIS305may be capable of reflecting and/or redirecting impinging signals via the reconfigurable elements, but may not be capable of generating and/or transmitting signals). Alternatively, in some examples, the RIS305and/or the RIS controller310may have transmit capabilities (e.g., the RIS305may be capable of reflecting and/or redirecting impinging signals via the reconfigurable elements and may be capable of generating and/or transmitting signals). For example, the RIS305and/or the RIS controller310may include one or more antennas and/or antenna elements for receiving and/or transmitting signals.

For example, as shown inFIG.3, the base station110may transmit a signal315. The signal315may be transmitted in a spatial direction toward the RIS305. The RIS305may configure the reconfigurable elements of the RIS305to reflect and/or redirect the signal315in a desired spatial direction and/or with one or more desired signal characteristics (e.g., beam width, phase, amplitude, frequency, and/or polarization). For example, as shown by reference number320, the RIS305may be capable of reflecting the signal315in one or more spatial directions. Although multiple beams are shown inFIG.3representing different beam states or beam directions of the RIS305, the RIS305may be capable of reflecting a signal with one beam state or one beam direction at a time. For example, in one case, as shown by reference number325, the RIS305may be configured to reflect the signal315using a first beam state (e.g., beam state 1). “Beam state” may refer to a spatial direction and/or a beam of a reflected signal (e.g., a signal reflected by the RIS305). The first beam state may cause the signal315to be reflected in a spatial direction toward a first UE120(e.g., UE 1). As shown by reference number330, in another case, the RIS305may be configured to reflect the signal315using a second beam state (e.g., beam state 2). The second beam state may cause the signal315to be reflected in a spatial direction toward a second UE120(e.g., UE 2).

The RIS305may be deployed in a wireless network (such as the wireless network100) to improve communication performance and efficiency. For example, the RIS305may enable a transmitter (e.g., a base station110or a UE120) to control the scattering, reflection, and refraction characteristics of signals transmitted by the transmitter, to overcome the negative effects of wireless propagation. For example, the RIS305may effectively control signal characteristics (e.g., spatial direction, beam width, phase, amplitude, frequency, and/or polarization) of an impinging signal without a need for complex decoding, encoding, and radio frequency processing operations. Therefore, the RIS305may provide increased channel diversity for propagation of signals in a wireless network. The increased channel diversity provides robustness to channel fading and/or blocking, such as when higher frequencies are used by the base station110and/or the UE120(e.g., millimeter wave frequencies and/or sub-terahertz frequencies). Moreover, as the RIS305does not need to perform complex decoding, encoding, and radio frequency processing operations, the RIS305may provide a more cost and energy efficient manner of reflecting and/or redirecting signals in a wireless network (e.g., as compared to other mechanisms for reflecting and/or redirecting signals, such as a relay device).

FIG.4is a diagram illustrating an example400of communication links in a wireless network that includes an RIS, in accordance with the present disclosure. As shown, example400includes a base station110, a UE120, and the RIS305. The RIS305may be controlled and/or configured by the RIS controller310.

As shown inFIG.4, the UE120may receive a communication (e.g., data and/or control information) directly from the base station110as a downlink communication. Additionally, or alternatively, the UE05may receive a communication (e.g., data and/or control information) indirectly from the base station110via the RIS305. For example, the base station110may transmit the communication in a spatial direction toward the RIS305, and the RIS305may redirect or reflect the communication to the UE120.

In some examples, the UE120may communicate directly with the base station110via a direct link405. For example, a communication may be transmitted via the direct link405. A communication transmitted via the direct link405between the UE120and the base station110does not pass through and is not reflected or redirected by the RIS305. In some examples, the UE120may communicate indirectly with the base station110via an indirect link410. For example, a communication may be transmitted via different segments of the indirect link410. A communication transmitted via the indirect link410between the UE120and the base station110is reflected and/or redirected by the RIS305. As shown inFIG.4and by reference number415, the base station110may communicate with the RIS305(e.g., with the RIS controller310) via a control channel. For example, the base station110may indicate, in an RIS control message, spatial direction(s) and/or signal characteristics for signals reflected by the RIS305. The RIS controller310may configure reconfigurable elements of the RIS305in accordance with the RIS control message. In some examples, the RIS control message may indicate information associated with the wireless network, such as a frame structure, time synchronization information, and/or slot boundaries, among other examples. Using the communication scheme shown inFIG.4may improve network performance and increase reliability by providing the UE120with link diversity for communicating with the base station110.

In some cases, the UE120may receive a communication (e.g., the same communication) from the base station110via both the direct link405and the indirect link410. In other cases, the base station110may select one of the links (e.g., either the direct link405or the indirect link410), and may transmit a communication to the UE120using only the selected link. Alternatively, the base station110may receive an indication of one of the links (e.g., either the direct link405or the indirect link410), and may transmit a communication to the UE120using only the indicated link. The indication may be transmitted by the UE120and/or the RIS305. In some examples, such selection and/or indication may be based at least in part on channel conditions and/or link reliability.

However, channel characteristics of the direct link405and the indirect link410may be different. For example, the direct link405and the indirect link410may be distinguishable in the spatial domain and/or the time domain. Additionally, or alternatively, the direct link405and the indirect link410may be associated with different Doppler characteristics (e.g., Doppler spread and/or Doppler shift). Therefore, the direct link405and the indirect link410may need to be separately maintained. For example, separate beam management (e.g., separate beam acquisition and/or beam tracking) may need to be performed for the direct link405and the indirect link410. As another example, transmit and/or receive processing of signals associated with the direct link405and the indirect link410may be different due to different path delays and/or Doppler characteristics, and/or due to separate time and/or frequency synchronizations of the direct link405and the indirect link410. Moreover, transmit power allocation for the direct link405and the indirect link410may be different due to different fading conditions of the direct link405and the indirect link410. As a result, the direct link405and the indirect link410may be maintained simultaneously, but may need to be treated separately (e.g., by the base station110and/or the UE120).

Wireless communication systems may use a variety RATs, such as Global System for Mobility (GSM), UMTS, LTE, and NR. Typically, RATs can be configured to provide security functionality such as ciphering and integrity protection, which may be applied to both a control plane (e.g., radio resource control (RRC) signaling through a signaling radio bearer) and a user plane (e.g., a data radio bearer) in a packet data convergence protocol (PDCP) layer. Various radio access technologies may also provide access control through authentication (e.g., via Access Security Management Entity keys or another suitable system).

However, some scheduled communications are not typically protected, such as medium access control (MAC) signaling (e.g., MAC control element (MAC-CE) signaling), broadcast information (e.g., system information block (SIB) signals), and paging information, and/or downlink communication channels (e.g., the physical downlink control channel (PDCCH) and the physical downlink shared channel (PDSCH)), among other examples. MAC signaling, broadcast information (e.g., SIB signals), and paging information are typically not protected by security functionalities because speed of communication (e.g., minimizing transfer delay) is judged more important than security for these signals. However, the signals provided in the PDCCH and PDSCH may include control information and content data (e.g., voice, and/or content for user services), and thus security may be more important for these signals. Malicious intruders or jammers may hinder or hijack the unprotected signals by fabricating a transmission with the same format (e.g., an appropriate PDCCH or PDSCH format). Without security protection, a wireless device intended to receive the PDCCH or PDSCH signals may be unable to distinguish between true and fabricated transmissions.

Some techniques and apparatuses described herein enable security enhancements using an RIS. For example, an RIS may use a modulation signature (e.g., watermarking) to insert a signature or a security key that can be used (e.g., by a UE) to authenticate a message that has been reflected or redirected by the RIS. For example, the RIS may be configured (e.g., by a base station) with a first security key. The RIS may insert the first security key into a signal using modulation (e.g., phase modulation, amplitude modulation, and/or other types of modulation). A UE may receive a signal redirected by the RIS (e.g., that has been modulated with a modulation signature that identifies the first security key). The UE may decode the signal to obtain the first security key. The UE may receive a signal transmitted on a downlink control channel (e.g., a PDCCH). The signal associated with the PDCCH may indicate a second security key. In some aspects, a PDCCH signal may include the second security key in a payload of the PDCCH signal. The PDCCH signal may be modulated by an RIS using a modulation signature, such that the UE may obtain the first security key based on the modulation signature and may obtain the second security key based on the payload of the PDCCH signal. The UE may receive a signal transmitted on a downlink shared channel (e.g., a PDSCH). The PDSCH signal may include a third security key (e.g., in a payload of the PDSCH signal). The PDSCH signal may be redirected to the UE by the RIS. The UE may authenticate the PDSCH signal based on the first security key, the second security key, and the third security key. For example, the UE may use an authentication function that uses the first security key and the second security key as inputs. The UE may compare an output of the authentication function to the third security key. If the output of the authentication function and the third security key match (e.g., are the same), then the UE120may determine that the PDSCH signal is authentic. If the output of the authentication function and the third security key do not match (e.g., are not the same), then the UE120may determine that the PDSCH signal is not authentic (e.g., and may block, or not permit further communication with, a device associated with the PDSCH signal).

As a result, a security associated with signals redirected by an RIS may be improved. For example, the UE may be enabled to identify fake and/or fabricated transmissions associated with the RIS and may be enabled to block or not receive further communications from the device that transmitted the fake and/or fabricated transmissions. Some techniques and apparatuses described herein enable improved security for MAC signaling, broadcast signaling, and/or paging signaling associated with an RIS.

FIG.5is a diagram illustrating an example500associated with security enhancements associated with an RIS, in accordance with the present disclosure. As shown inFIG.5, a base station110and a UE120may communicate with one another in a wireless network, such as the wireless network100. As shown inFIG.5, in some aspects, the UE120and the base station110may communicate via an RIS502. The RIS502may be similar to the RIS305and/or the RIS160described elsewhere herein.

As shown by reference number504, the base station110may transmit (e.g., using controller/processor240, transmit processor220, TX MIMO processor230, MOD232, antenna234, and/or memory242), and the UE120(e.g., using antenna252, DEMOD254, MIMO detector256, receive processor258, controller/processor280, and/or memory282) and/or the RIS502may receive, configuration information. In some aspects, the UE120may receive configuration information from another device (e.g., from another base station or another UE). In some aspects, the UE120may receive the configuration information via system information signaling, RRC signaling and/or MAC signaling (e.g., MAC-CEs). In some aspects, the configuration information may include an indication of one or more configuration parameters (e.g., already known to the UE120) for selection by the UE120and/or explicit configuration information for the UE120to use to configure itself.

In some aspects, the configuration information may indicate that an indirect link between the base station110, the RIS502, and the UE120is to be established and/or maintained. In some aspects, the configuration information may indicate a security enhancement, using the RIS502, for signaling between the base station110and the UE120(e.g., using the security keys described herein). The security enhancement may be enabled and/or activated via the configuration information. In some aspects, the security enhancement may be enabled and/or activated in a different message (e.g., based at least in part on a report provided by the UE120, as described in more detail elsewhere herein). As used herein, “security enhancement” may refer to authenticating PDSCH messages using a security key that is added to a signal by an RIS using a modulation signature, as described in more detail elsewhere herein. In some aspects, the security enhancement may be a physical layer security enhancement.

In some aspects, the configuration information may indicate that the UE120is to transmit an RIS report to the base station110(e.g., associated with the RIS502and/or other RISs deployed in the wireless network). The RIS report may be a report for a link associated with the RIS502(and/or other RISs deployed in the wireless network). The report may indicate an identifier associated with the RIS502and/or one or more measurements of one or more signals transmitted via the link with the RIS502, among other examples. The RIS report may enable the base station110to determine whether the security enhancement described herein is to be activated for the UE120, as described in more detail elsewhere herein. In some aspects, the configuration information may indicate one or more threshold values and/or conditions associated with using the security enhancement described herein. For example, the configuration information may indicate one or more threshold values associated with a link quality of the RIS link associated with the RIS502. If a measured quality (e.g., a measured RSRQ or other link quality parameter) of the RIS link satisfies the one or more threshold values, then the UE120and/or the base station110may determine that the security enhancement may be used for the RIS link.

In some aspects, the configuration information may indicate an authentication function associated with the security enhancement. The authentication function may be a function that enables the UE120to obtain an authentication key from one or more security keys. The authentication key may be compared to a security key included in a PDSCH message to authenticate the PDSCH message, as described in more detail elsewhere herein. In some other aspects, the authentication function may be pre-configured on the UE120(e.g., without receiving any signaling indicating the authentication function).

In some aspects, the configuration information may indicate a modulation signature associated with the RIS502. “Modulation signature” may refer to a pattern or sequence of modulation added to a signal that is reflected or redirected by the RIS502. The modulation signature may also be referred to as an RIS watermark. For example, the modulation signature may be a phase modulation signature, a polarization modulation signature, and/or an amplitude modulation signature, among other examples. In some aspects, the configuration information may indicate a beam state or a beam direction of the RIS502that is associated with the modulation signature (e.g., multiple modulation signatures may be indicated for multiple beam states and/or beam directions of the RIS502). In some aspects, the configuration information may indicate a pattern or sequence associated with the modulation signature. In some aspects, the configuration information may indicate that the RIS502is to modulate a signal reflected by the RIS, in accordance with the modulation signature, at symbol boundaries and/or in symbols that contain a reference signal (e.g., a DMRS, a phase tracking reference signal (PTRS), and/or a polarization detection reference signal). In some aspects, the configuration information may configure the reference signal that is to be associated with the signal to be reflected by the RIS502. For example, if the modulation signature is a phase modulation signature, then the configuration information may configure DMRSs and/or PTRSs to be transmitted with the signal. Similarly, if the modulation signature is a polarization modulation signature, then the configuration information may configure polarization detection reference signals and/or other reference signals to be transmitted with the signal. The reference signals may enable the UE120to identify and/or detect the modulation of the signal. In some aspects, the modulation signature may identify a security key, as described in more detail elsewhere herein. Additionally, or alternatively, the modulation signature may identify an identifier of the RIS502.

As shown by reference number506, the UE120may configure (e.g., using controller/processor280and/or memory282) the UE120for communicating with the base station110and/or with the RIS502. In some aspects, the UE120may configure the UE120based at least in part on the configuration information. In some aspects, the UE120may be configured to perform one or more operations described herein. As shown by reference number508, the RIS502(and/or an RIS controller of the RIS502) may configure the RIS502for communicating with the base station110and/or the UE120. In some aspects, the RIS502(and/or an RIS controller of the RIS502) may configure the RIS502based at least in part on the configuration information. In some aspects, the RIS502may be configured to perform one or more operations described herein.

In some aspects, the UE120may transmit (e.g., using controller/processor280, transmit processor264, TX MIMO processor266, MOD254, antenna252, and/or memory282), and the base station110may receive (e.g., using antenna234, DEMOD232, MIMO detector236, receive processor238, controller/processor240, and/or memory242), a capability message indicating whether the UE120supports the security enhancement described herein. For example, the UE120may transmit, and the base station110may receive, a message indicating whether the UE120is capable of authenticating PDSCH messages using a security key that is indicated by a signal via a modulation signature added by an RIS. In some aspects, the configuration information may be based at least in part on the capability message (e.g., the base station110may configure the UE120to use the security enhancement only if the UE120indicates that the UE120supports the security enhancement). The UE120may transmit the capability message via RRC signaling and/or physical uplink control channel (PUCCH) signaling, among other examples.

As shown by reference number510, the base station110may transmit (e.g., using controller/processor240, transmit processor220, TX MIMO processor230, MOD232, antenna234, and/or memory242) one or more signals. The one or more signals may be transmitted on a beam associated with, and/or in a spatial direction toward, the RIS502. The one or more signals may be reference signals. In some aspects, the one or more signals may be an RIS reference signal. The RIS reference signal may be associated with measuring link parameters (e.g., link quality, signal strength, and/or other parameters) of an RIS link (e.g., an indirect link associated with an RIS). The one or more signals may be used by the UE120to measure link parameters and/or to identify the RIS link.

As shown by reference number512, the RIS502may reflect and/or redirect the one or more signals toward the UE120(e.g., using a beam associated with the UE120and/or in a spatial direction toward the UE120). The RIS502may modulate the signal (e.g., the impinging signal that arrives at the RIS502) using a modulation signature that identifies an identifier associated with the RIS502. For example, the RIS502may modulate the signal in phase (e.g., for a phase modulation signature), may modulate a polarization of the signal (e.g., for a polarization modulation signature), and/or may modulate an amplitude of the signal (e.g., for an amplitude modulation signature). For example, for a phase modulation signature and/or a polarization modulation signature, the RIS502may modulate the signal in symbols of the signal that include a reference signal (e.g., a DMRS, a PTRS, and/or a polarization detection reference signal). As another example, for a polarization modulation signature, the RIS502may modulate a polarization state of the signal from a first polarization state of the signal as transmitted by the base station110to a second polarization state of the signal. A polarization state may include an angle of polarization or a polarization mode. For an amplitude modulation signature, the RIS502may modulate the amplitude of the signal by attenuating the amplitude of the signal in accordance with a pattern (e.g., the amplitude modulation signature) that identifies the RIS502. The RIS502may modulate the amplitude of the signal by puncturing the signal at one or more symbols of the signal, and/or by modulating a spatial direction of the signal.

As shown by reference number514, the UE120may receive (e.g., using antenna252, DEMOD254, MIMO detector256, receive processor258, controller/processor280, and/or memory282) a signal (e.g., a modulated signal) that is redirected or reflected by the RIS502. The signal may be modulated by the RIS502using the modulation signature, as described in more detail elsewhere herein. The UE120may demodulate and/or decode the signal (e.g., the modulated signal) to identify that the signal was transmitted via a link that includes the RIS502. For example, the UE120may detect phase changes, polarization changes, and/or amplitude changes in the signal. The UE120may detect that the phase changes, polarization changes, and/or amplitude changes vary in a pattern or sequence that corresponds to the modulation signature associated with the RIS502. Therefore, the UE120may identify that the signal was reflected and/or redirected by the RIS502. In some aspects, the UE120may decode the one or more signals based on decoding information provided by the base station110(e.g., via the configuration information). For example, a decoding method may be indicated to the UE120by the base station110. In some other aspects, the decoding method may be defined (e.g., such that no signaling is required).

In some aspects, the UE120may measure (e.g., using antenna252, DEMOD254, MIMO detector256, receive processor258, controller/processor280, and/or memory282) the one or more signals (e.g., using an RIS reference signal). The UE120may measure one or more link parameters such as a link quality (e.g., an RSRQ), a signal strength (e.g., an RSRP), a signal-to-noise ratio (SNR), and/or other link parameters. In some other aspects, the UE120may not measure the one or more signals. The UE120may identify an RIS identifier (e.g., indicated by the modulation signature) associated with the one or more signals.

As shown by reference number516, the UE120may transmit (e.g., using controller/processor280, transmit processor264, TX MIMO processor266, MOD254, antenna252, and/or memory282), and the base station110may receive (e.g., using antenna234, DEMOD232, MIMO detector236, receive processor238, controller/processor240, and/or memory242), a report. The report may be an RIS report. In some aspects, the report may indicate an identifier associated with the RIS502and/or one or more measurements of one or more signals transmitted via the link with the RIS502, among other examples. In some aspects, the report may indicate whether the security enhancement described herein is to be activated. For example, in some aspects, the UE120may determine whether the measurement(s) of the one or more signals satisfy a threshold (e.g., a threshold indicated by the configuration information or a pre-defined threshold, such as a threshold defined, or otherwise fixed, by a wireless communication standard). If the measurement(s) satisfy the threshold, then the UE120may determine that the security enhancement described herein is to be activated. If the measurement(s) do not satisfy the threshold, then the UE120may determine that the security enhancement described herein is not to be activated.

The report may enable the base station110to determine (e.g., using controller/processor240and/or memory242) whether the security enhancement described herein should be activated and/or applied. For example, the report may indicate whether the RIS link (e.g., associated with the RIS502) has a suitable link quality to support the security enhancement. For example, if the security enhancement were to be used when the link quality is poor (e.g., does not satisfy a threshold), then the UE120may be unable to obtain or receive one or more security keys for the security enhancement. As a result, the UE120may be unable to authenticate PDSCH messages and/or may incorrectly determine that a PDSCH message is not authenticated. Therefore, enabling the security enhancement based at least in part on the link quality of the RIS link may ensure that the UE120is able to properly apply the security enhancement and/or authenticate PDSCH messages, as described in more detail elsewhere herein. For example, in some cases, the UE120may receive reflected signals from multiple RISs (e.g., with different identifiers), which may accumulate at the UE120and may be indistinguishable from each other. As another example, when a line-of-sight (LoS) path is a dominant path (e.g., is associated with a highest link parameter), the UE120may be unable to identify an RIS signature and/or a modulation signature. As a result, the UE120may be unable to receive and/or decode a modulation signature applied by the RIS502in some scenarios. The report transmitted by the UE120may enable the base station110to identify whether one of the scenarios (e.g., that prevents or reduces the UE's120ability to receive and/or decode a modulation signature applied by the RIS502) is currently present.

As shown by reference number518, the base station110may determine (e.g., using controller/processor240and/or memory242) whether the security enhancement is to be used. The base station110may determine whether the security enhancement is to be used based at least in part on the report (e.g., the RIS report) transmitted by the UE120. For example, the report may indicate one or more RIS identifiers. The base station110may measure and/or identify a measurement of an RIS link associated with an RIS identifier indicated by the report. For example, the base station110may measure and/or identify a measurement of an RIS link associated with the RIS502. The base station110may determine whether the measurement of the RIS link (e.g., a measurement of a link quality of the RIS link) satisfies a threshold. If the measurement satisfies the threshold, then the base station110may determine that the security enhancement is to be used. If the measurement does not satisfy the threshold, then the base station110may determine that the security enhancement should not be used. In some aspects, as described above, the UE120may determine whether the RIS link is suitable for the security enhancement. The UE120may indicate, in the report, whether the RIS link is suitable for the security enhancement (e.g., as described in more detail elsewhere herein). In such examples, the base station110may determine whether the security enhancement is to be used based at least in part on the indication in the report from the UE120.

As shown by reference number520, the base station110may transmit (e.g., using controller/processor240, transmit processor220, TX MIMO processor230, MOD232, antenna234, and/or memory242), and the RIS502may receive (e.g., the RIS controller of the RIS502may receive) an indication of a first security key associated with the RIS502. The first security key may be referred to herein as “S3.” The first security key may be a security key that is to be added, using a modulation signature, to signals reflected or redirected by the RIS502. As used herein, “security key” may refer to a unique key or code. For example, a security key may include a random sequence of numbers and/or letters, a hash key, an encryption key, an access security management entity (ASME) key, a sequence of bits, a specific waveform, and/or a PDCCH DMRS sequence, among other examples.

The base station110may configure the RIS502with the first security key based at least in part on determining that the security enhancement is to be used, as described in more detail elsewhere herein. For example, the base station110may determine that the security enhancement is to be used based at least in part on the report transmitted by the UE120. The base station110may transmit, to the RIS502, an indication of the first security key to cause the RIS502to insert the first security key into one or more signals using a modulation signature. In some aspects, the first security key may be based at least in part on an identifier associated with the RIS502. For example, the base station110may determine and/or generate the first security key using the identifier associated with the RIS502.

In some aspects, the base station110may indicate one or more beams and/or a spatial direction for which the RIS502is to insert the first security key. For example, the one or more beams and/or the spatial direction may be associated with (e.g., may be toward) the UE120. The base station110may indicate that the RIS502is to insert the first security key (e.g., using modulation) into signals reflected and/or redirected in the direction of the one or more beams and/or the spatial direction associated with the UE120. In other words, the RIS502may be configured to insert the first security key for signals associated with some beams and/or spatial directions and may be configured to not insert the first security key for signals associated with other beams and/or spatial directions.

As shown by reference number522, the base station110may transmit (e.g., using controller/processor240, transmit processor220, TX MIMO processor230, MOD232, antenna234, and/or memory242) a control message (e.g., a signal associated with a downlink control channel), such as a PDCCH message (e.g., a message transmitted via the PDCCH). The base station110may transmit the control message using a beam associated with, or in a spatial direction toward, the RIS502. The control message may include a second security key. For example, the second security key may be included in a payload of the control message. The second security key may be referred to herein as “S1.” The base station110may determine the second security key. In some aspects, the base station110may transmit the control message to the UE120using a direct link (e.g., without using the RIS502). In some other aspects, the control message may be redirected and/or reflected toward the UE120by the RIS502. The control message may be a message that schedules one or more PDSCH messages.

In some aspects, as shown by reference number524, the RIS502may modulate the signal (e.g., the signal associated with the control message) using a modulation signature to insert the first security key. For example, the RIS502may insert the first security key into a PDCCH signal. For example, the signal may be reflected or redirected by the RIS502to the UE120. The RIS502may modulate the signal (e.g., the impinging signal that arrives at the RIS502) using the modulation signature. The RIS502may modulate the signal based at least in part on the signal being associated with a beam and/or spatial direction toward the UE120. For example, the RIS502may be configured (e.g., by the base station110) to modulate signals (e.g., PDCCH signals and/or other signals) that are to be redirected and/or reflected toward the UE120(e.g., to insert the first security key and to enable the security enhancement described herein).

For example, the RIS502may modulate a phase of the signal (e.g., for a phase modulation signature), may modulate a polarization of the signal (e.g., for a polarization modulation signature), and/or may modulate an amplitude of the signal (e.g., for an amplitude modulation signature). For example, for a phase modulation signature and/or a polarization modulation signature, the RIS502may modulate the signal in symbols of the signal that include a reference signal (e.g., a DMRS, a PTRS, and/or a polarization detection reference signal). For a polarization modulation signature, the RIS502may modulate a polarization state of the signal from a first polarization state of the signal as transmitted by the base station110to a second polarization state of the signal. For an amplitude modulation signature, the RIS502may modulate the amplitude of the signal by attenuating the amplitude of the signal in accordance with a pattern (e.g., the amplitude modulation signature) that identifies the first security key. The RIS502may modulate the amplitude of the signal by puncturing the signal at one or more symbols of the signal, and/or by modulating a spatial direction of the signal. In some aspects, the RIS502may use a modulation signature that identifies the first security key and identifies the RIS502. In some aspects, the signal modulated by the RIS502using the modulation signature may be a signal associated with the control message (e.g., that includes the second security key in the payload of the control message) and/or may be a signal associated with another PDCCH message.

As shown by reference number526, the UE120may receive (e.g., using antenna252, DEMOD254, MIMO detector256, receive processor258, controller/processor280, and/or memory282) the control message that includes the second security key. In some aspects, the signal of the control message may be modulated using the modulation signature that identifies the first security key. In some aspects, the control message that includes the second security key may not be modulated by the RIS502and/or may be transmitted via a direct link between the UE120and the base station110. In such examples, the UE120may receive another signal (e.g., another PDCCH signal) that is modulated using the modulation signature.

The UE120may receive the control message and/or the other message (e.g., using antenna252, DEMOD254, MIMO detector256, receive processor258, controller/processor280, and/or memory282) to obtain the first security key and the second security key. For example, the UE120may decode the control message to identify the second security key in the payload of the control message. Similarly, the UE120may decode the signal modulated by the RIS502to identify the modulation signature. The UE120may determine the first security key based at least in part on the modulation signature (e.g., the modulation signature may include a pattern or sequence that identifies the first security key). The first security key and the second security key may be used when decoding data scheduled by the control message. For example, the data may be broadcast information or other signaling. The UE120may use the first security key and the second security key to decode and authenticate the data, as described in more detail elsewhere herein.

As shown by reference number528, the base station110may transmit (e.g., using controller/processor240, transmit processor220, TX MIMO processor230, MOD232, antenna234, and/or memory242) another signal (e.g., a second signal) that includes a third security key. The third security key may be referred to herein as “S2.” The signal that includes the third security key may be a data signal and/or a PDSCH signal. For example, the signal that includes the third security key may be associated with broadcast signaling, SIB signaling, MAC signaling, and/or paging signaling, among other examples. In some aspects, the base station110may determine the third security key. For example, the base station110may determine the third security key based at least in part on the first security key and the second security key. In some aspects, the base station110may determine the third security key to be the output of an authentication function when the first security key and the second security key are provided as inputs to the authentication function.

In some aspects, the second security key and/or the third security key may be based at least in part on a fourth security key. The fourth security key may be referred to herein as “S0.” The fourth security key may be a security key associated with another type of signaling. For example, the fourth security key may be an access security key. The fourth security key may be associated with UE-specific data security (e.g., ciphering and integrity protection) and/or MAC signaling security, among other examples. For example, the fourth security key may be established and/or generated as part of a connection establishment procedure between the UE120and the base station110. For example, the base station110may transmit, and the UE120may receive, an indication of the fourth security key (e.g., as part of the connection establishment procedure). In some aspects, the second security key (e.g., the security key included in the PDCCH signal or the control signal) may be derived from S0 and S1 (e.g., may be derived from the key established between the UE120and the base station and a random security key). In some other aspects, the second security key may be a random security key and may not be based at least in part on S0. In some aspects, the third security key (e.g., the security key included in the PDSCH signal) may be derived as a function of S0 and/or S2. In some aspects, at least one of the second security key or the third security key may be based at least in part on S0 (e.g., at least one of the second security key or the third security key may be a function of S0).

In some aspects, as shown by reference number530, the RIS502may reflect and/or redirect the signal (e.g., the PDSCH signal and/or the signal that includes the third security key in a payload of the third signal) toward the UE120. For example, the RIS502may redirect the signal using a beam and/or spatial direction associated with the UE120. In some aspects, the RIS502may modulate the signal to insert the modulation signature (e.g., in a similar manner as described above). In some other aspects, the RIS502may not modulate the signal (e.g., the PDSCH signal and/or the signal that includes the third security key in a payload of the third signal). In some aspects, the signal may be transmitted via a direct link between the UE120and the base station110(e.g., via a link that does not include the RIS502).

As shown by reference number532, the UE120may authenticate the signal based at least in part on the first security key, the second security key, and the third security key (e.g., using controller/processor280and/or memory282). For example, the UE120may receive and decode the signal to obtain the third security key. The UE120may generate, using an authentication function, an authentication key based at least in part on the first security key and the second security key. In some aspects, the authentication function may be or may include a one-way function, a key derivation function, a secure hash function, or another suitable function. In some aspects, the authentication function may include a process, algorithm, mathematical transform, or another operation or series of operations, which may be provisioned in the UE120(e.g., by the base station110). In some embodiments, the base station110may statically provision the UE120with the authentication function. In some other aspects, the base station110may provision the UE120with the authentication function dynamically. For example, the base station110may change or provide a new authentication function to the UE120from time to time.

The UE120may authenticate the signal based at least in part on whether the authentication key matches the third security key. For example, if the authentication key matches the third security key, then the UE120may determine that the signal (e.g., that includes the third security key in the payload) is authentic. If the authentication key does not match the third security key, then the UE120may determine that the signal (e.g., that includes the third security key in the payload) is fake and/or fabricated (e.g., not authentic). For example, the UE120may perform a matching operation to determine whether the authentication key matches the third security key. For example, the matching operation may be expressed as S2=ƒa(S1, S3), where ƒa( ) is the authentication function. In some aspects, such as where at least one of the second security key or the third security key is based at least in part on S0, the matching operation may be expressed as S2=ƒa(S0, S1, S3).

If the UE120determines that the signal is authentic (e.g., based at least in part on the matching operation), then the UE120may enable communications with the base station110. If the UE120determines that the signal is not authentic (e.g., based at least in part on the matching operation), then the UE120may disable or block communications with the base station110. This may improve a security associated with the PDSCH signaling because the UE120is enabled to determine when signals transmitted via the PDSCH are authentic. As a result, a security associated with signals redirected by the RIS502may be improved. For example, the UE120may be enabled to identify fake and/or fabricated transmissions associated with the RIS502and may be enabled to block or not receive further communications from the device that transmitted the fake and/or fabricated transmissions. Some techniques and apparatus described herein enable improved security for MAC signaling, broadcast signaling, and/or paging signaling associated with an RIS502.

FIG.6is a diagram illustrating an example600associated with security enhancements with an RIS, in accordance with the present disclosure. As shown inFIG.6, a base station110may communicate with one or more UEs120(e.g., UE1 and UE2) in a wireless network, such as the wireless network100. The base station110and the UEs120may use an RIS605to communicate with one another. For example, the RIS605may reflect or redirect a signal to the base station110and/or the UEs120. The RIS605may be the same as, or similar to, the RIS502described in connection withFIG.5. The reconfigurable elements of the RIS605may be controlled and/or configured by an RIS controller610. The RIS controller610may be a control module (e.g., a controller and/or a processor) that is capable of configuring the electromagnetic characteristic(s) of each reconfigurable element of the RIS605(e.g., in a similar manner as described in connection withFIG.3).

As shown by reference number615, the base station110may transmit, and the RIS605and/or the RIS controller610may receive, an indication of the first security key (e.g., S3), in a similar manner as described in connection withFIG.5. For example, the base station110and/or the UE 1 may determine that the security enhancement described herein is to be used. Therefore, the base station110may configure the RIS605to insert the first security key into signals reflected and/or redirected toward the UE 1.

The base station110may transmit a signal620. The signal620may be transmitted in a spatial direction toward the RIS605. The RIS605may configure the reconfigurable elements of the RIS605to reflect and/or redirect the signal620in a desired spatial direction and/or with one or more desired signal characteristics (e.g., beam width, phase, amplitude, frequency, and/or polarization). Additionally, as shown by reference number625, the RIS605may modulate the signal620(e.g., in phase, polarization state, and/or amplitude). For example, the RIS605may modulate the signal620using a modulation signature to insert the first security key (e.g., S3) into a signal reflected and/or redirected by the RIS605. The RIS605may modulate the signal620using the modulation signature in a similar manner as described in connection withFIG.5.

Although multiple beams are shown inFIG.6representing different beam states or beam directions of the RIS605, the RIS605may be capable of reflecting a signal with one beam state or one beam direction at a time. For example, in one case, as shown by reference number630, the RIS305may be configured to reflect the signal620using a first beam state (e.g., beam state 1). The first beam state may cause the signal620to be reflected in a spatial direction toward a first UE120(e.g., UE 1). The reflected signal may be a modulated signal (e.g., modulated in accordance with the modulation signature) to identify the first security key. For example, the security enhancements described herein may be enabled or activated for the UE 1. Therefore, the RIS605may modulate the reflected signal to insert the first security key into the reflected signal. This may enable the UE 1 to receive and decode the reflected signal to obtain the first security key. The UE 1 may use the first security key (and/or additional security keys, as described in more detail elsewhere herein) to authenticate future messages transmitted by the base station110, as described in more detail in connection withFIG.5.

As shown by reference number635, in another case, the RIS605may be configured to reflect the signal620using a second beam state (e.g., beam state 2). The first beam state may cause the signal620to be reflected in a spatial direction toward a second UE120(e.g., UE 2). In some aspects, the security enhancements described herein may not be enabled and/or may not be activated for the UE 2. Therefore, as shown inFIG.6, the RIS605may reflect the signal620toward the UE 2 without modulating the signal620. In this way, the UE 2 may be enabled to decode the reflected signal. This provides additional flexibility for the base station110to enable the security enhancement for some UEs and to disable the security enhancement for other UEs (e.g., based at least in part on RIS link qualities associated with the different UEs).

FIG.7is a diagram illustrating an example process700performed, for example, by a UE, in accordance with the present disclosure. Example process700is an example where the UE (e.g., UE120) performs operations associated with security enhancements with an RIS.

As shown inFIG.7, in some aspects, process700may include receiving a first signal associated with a downlink control channel, wherein the first signal uses a modulation signature that identifies a first security key associated with an RIS, and wherein the first signal includes a second security key (block710). For example, the UE (e.g., using communication manager140and/or reception component1102, depicted inFIG.11) may receive a first signal associated with a downlink control channel, wherein the first signal uses a modulation signature that identifies a first security key associated with an RIS, and wherein the first signal includes a second security key, as described above.

As further shown inFIG.7, in some aspects, process700may include receiving a second signal associated with a downlink shared channel, wherein the second signal includes a third security key, and wherein the second signal is authenticated by the UE based at least in part on the first security key, the second security key, and the third security key (block720). For example, the UE (e.g., using communication manager140and/or reception component1102, depicted inFIG.11) may receive a second signal associated with a downlink shared channel, wherein the second signal includes a third security key, and wherein the second signal is authenticated by the UE based at least in part on the first security key, the second security key, and the third security key, as described above.

In a first aspect, process700includes decoding the second signal to authenticate the second signal using the first security key, the second security key, and the third security key.

In a second aspect, alone or in combination with the first aspect, decoding the second signal to authenticate the second signal includes generating, using an authentication function, an authentication key based at least in part on the first security key and the second security key, and authenticating the second signal based at least in part on whether the authentication key matches the third security key.

In a third aspect, alone or in combination with one or more of the first and second aspects, process700includes transmitting, to a base station, a report for a link associated with the RIS, wherein the report indicates at least one of an identifier associated with the RIS and one or more measurements of one or more signals transmitted via the link, and wherein the first signal using the modulation signature that identifies the first security key is based at least in part on the report.

In a fourth aspect, alone or in combination with one or more of the first through third aspects, process700includes measuring the one or more signals transmitted via the link using an RIS reference signal associated with the one or more signals to obtain the one or more measurements.

In a fifth aspect, alone or in combination with one or more of the first through fourth aspects, the first signal using the modulation signature that identifies the first security key is based at least in part on the one or more measurements satisfying a threshold.

In a sixth aspect, alone or in combination with one or more of the first through fifth aspects, the report includes an indication of whether the one or more measurements satisfy a threshold, and the first signal using the modulation signature that identifies the first security key is based at least in part on whether the one or more measurements satisfy the threshold.

In a seventh aspect, alone or in combination with one or more of the first through sixth aspects, the modulation signature is at least one of a phase modulation signature, a polarization modulation signature, or an amplitude modulation signature.

In an eighth aspect, alone or in combination with one or more of the first through seventh aspects, the first security key is based at least in part on an identifier associated with the RIS.

In a ninth aspect, alone or in combination with one or more of the first through eighth aspects, the modulation signature further identifies an identifier associated with the RIS.

In a tenth aspect, alone or in combination with one or more of the first through ninth aspects, process700includes receiving, from a base station, an indication of a fourth security key, wherein at least one of the second security key or the third security key is based at least in part on the fourth security key.

In an eleventh aspect, alone or in combination with one or more of the first through tenth aspects, receiving the indication of the fourth security key includes receiving, from the base station, the indication of the fourth security key as part of a connection establishment procedure with the base station.

In a twelfth aspect, alone or in combination with one or more of the first through eleventh aspects, the fourth security key is associated with at least one of UE-specific data security or medium access control signaling security.

In a thirteenth aspect, alone or in combination with one or more of the first through twelfth aspects, the first signal using the modulation signature that identifies the first security key is based at least in part on the first signal being associated with a beam state or a spatial direction that is associated with the UE.

FIG.8is a diagram illustrating an example process800performed, for example, by a base station, in accordance with the present disclosure. Example process800is an example where the base station (e.g., base station110) performs operations associated with security enhancements with an RIS.

As shown inFIG.8, in some aspects, process800may include transmitting, to an RIS, an indication of a first security key associated with the RIS, wherein the first security key is to be added, using a modulation signature, to signals reflected by the RIS (block810). For example, the base station (e.g., using communication manager150and/or transmission component1204, depicted inFIG.12) may transmit, to an RIS, an indication of a first security key associated with the RIS, wherein the first security key is to be added, using a modulation signature, to signals reflected by the RIS, as described above.

As further shown inFIG.8, in some aspects, process800may include transmitting a first signal that is associated with a downlink control channel, wherein the first signal includes a second security key, and wherein the first signal is to be reflected by the RIS (block820). For example, the base station (e.g., using communication manager150and/or transmission component1204, depicted inFIG.12) may transmit a first signal that is associated with a downlink control channel, wherein the first signal includes a second security key, and wherein the first signal is to be reflected by the RIS, as described above.

As further shown inFIG.8, in some aspects, process800may include transmitting a second signal that is associated with a downlink shared channel, wherein the second signal includes a third security key, and wherein the first security key, the second security key, and the third security key enable a user equipment (UE) to authenticate the second signal (block830). For example, the base station (e.g., using communication manager150and/or transmission component1204, depicted inFIG.12) may transmit a second signal that is associated with a downlink shared channel, wherein the second signal includes a third security key, and wherein the first security key, the second security key, and the third security key enable a UE to authenticate the second signal, as described above.

In a first aspect, process800includes receiving, from the UE, a report for a link associated with the RIS, wherein the report indicates at least one of an identifier associated with the RIS and one or more measurements of one or more signals transmitted via the link, and wherein transmitting, to the RIS, the indication of the first security key is based at least in part on the report.

In a second aspect, alone or in combination with the first aspect, process800includes identifying a link quality associated with the link based at least in part on the one or more measurements.

In a third aspect, alone or in combination with one or more of the first and second aspects, transmitting, to the RIS, the indication of the first security key is based at least in part on the one or more measurements satisfying a threshold.

In a fourth aspect, alone or in combination with one or more of the first through third aspects, the report includes an indication of whether the one or more measurements satisfy a threshold, and transmitting, to the RIS, the indication of the first security key is based at least in part on whether the one or more measurements satisfy the threshold.

In a fifth aspect, alone or in combination with one or more of the first through fourth aspects, the modulation signature is at least one of a phase modulation signature, a polarization modulation signature, or an amplitude modulation signature.

In a sixth aspect, alone or in combination with one or more of the first through fifth aspects, the first security key is based at least in part on an identifier associated with the RIS.

In a seventh aspect, alone or in combination with one or more of the first through sixth aspects, process800includes transmitting, to the UE, an indication of a fourth security key, wherein at least one of the second security key or the third security key is based at least in part on the fourth security key.

In an eighth aspect, alone or in combination with one or more of the first through seventh aspects, transmitting the indication of the fourth security key includes transmitting, to the UE, the indication of the fourth security key as part of a connection establishment procedure with the UE.

In a ninth aspect, alone or in combination with one or more of the first through eighth aspects, the fourth security key is associated with at least one of UE-specific data security or medium access control signaling security.

In a tenth aspect, alone or in combination with one or more of the first through ninth aspects, transmitting, to the RIS, the indication of the first security key includes transmitting an indication of a beam state or a spatial direction to which the first security key is to be added by the RIS.

FIG.9is a diagram illustrating an example process900performed, for example, by an RIS, in accordance with the present disclosure. Example process900is an example where the RIS (e.g., RIS160, RIS502, and/or RIS605) performs operations associated with security enhancements with an RIS.

As shown inFIG.9, in some aspects, process900may include receiving, from a base station, an indication of a first security key associated with the RIS, wherein the first security key is to be added, using a modulation signature, to signals reflected by the RIS (block910). For example, the RIS (e.g., using communication manager170and/or reception component1302, depicted inFIG.13) may receive, from a base station, an indication of a first security key associated with the RIS, wherein the first security key is to be added, using a modulation signature, to signals reflected by the RIS, as described above.

As further shown inFIG.9, in some aspects, process900may include receiving, from the base station, a first signal associated with a downlink control channel, wherein the first signal includes a second security key (block920). For example, the RIS (e.g., using communication manager170and/or reception component1302, depicted inFIG.13) may receive, from the base station, a first signal associated with a downlink control channel, wherein the first signal includes a second security key, as described above.

As further shown inFIG.9, in some aspects, process900may include redirecting, to a UE, the first signal by including the modulation signature that identifies the first security key in the first signal (block930). For example, the RIS (e.g., using communication manager170and/or redirection component1308, depicted inFIG.13) may redirect, to a UE, the first signal by including the modulation signature that identifies the first security key in the first signal, as described above.

As further shown inFIG.9, in some aspects, process900may include redirecting, to the UE, a second signal, wherein the second signal includes a third security key, and wherein the first security key, the second security key, and the third security key enable the UE to authenticate the second signal (block940). For example, the RIS (e.g., using communication manager170and/or redirection component1308, depicted inFIG.13) may redirect, to the UE, a second signal, wherein the second signal includes a third security key, and wherein the first security key, the second security key, and the third security key enable the UE to authenticate the second signal, as described above.

In a first aspect, the modulation signature is at least one of a phase modulation signature, a polarization modulation signature, or an amplitude modulation signature.

In a second aspect, alone or in combination with the first aspect, the modulation signature is a polarization modulation signature, and redirecting the first signal includes modulating a polarization state of the first signal from a first polarization state of the first signal as transmitted by the base station to a second polarization state of the first signal, wherein the polarization state includes an angle of polarization or a polarization mode.

In a third aspect, alone or in combination with one or more of the first and second aspects, the modulation signature identifies the first security key and an identifier associated with the RIS.

In a fourth aspect, alone or in combination with one or more of the first through third aspects, the first security key is based at least in part on an identifier associated with the RIS.

In a fifth aspect, alone or in combination with one or more of the first through fourth aspects, at least one of the second security key or the third security key is based at least in part on a fourth security key.

In a sixth aspect, alone or in combination with one or more of the first through fifth aspects, the fourth security key is established as part on a connection establishment procedure between the base station and the UE.

In a seventh aspect, alone or in combination with one or more of the first through sixth aspects, redirecting the first signal including the modulation signature is based at least in part on a quality of a link between the RIS and the UE satisfying a threshold.

In an eighth aspect, alone or in combination with one or more of the first through seventh aspects, receiving the indication of the first security key includes receiving an indication of a beam state or a spatial direction to which the first security key is to be added by the RIS, and redirecting the first signal by including the modulation signature that identifies the first security key in the first signal is based at least in part on the first signal being redirected using the beam state or the spatial direction.

FIG.10is a diagram illustrating an example process1000performed, for example, by a UE, in accordance with the present disclosure. Example process1000is an example where the UE (e.g., UE120) performs operations associated with security enhancements with an RIS.

As shown inFIG.10, in some aspects, process1000may include receiving a first signal that is modulated by an RIS using a modulation signature, wherein the modulation signature identifies a first security key (e.g., S3) (block1010). For example, the UE (e.g., using communication manager140and/or reception component1102, depicted inFIG.11) may receive a first signal that is modulated by an RIS using a modulation signature, wherein the modulation signature identifies a first security key, as described above. The modulation signature may be a phase modulation signature, a polarization modulation signature, and/or an amplitude modulation signature, among other examples.

As shown inFIG.10, in some aspects, process1000may include receiving a PDCCH signal indicating a second security key (e.g., S1) (block1020). For example, the UE (e.g., using communication manager140and/or reception component1102, depicted inFIG.11) may receive a PDCCH signal indicating a second security key (e.g., S1), as described above. In some aspects, the PDCCH signal may be the first signal. In some aspects, the PDCCH signal may indicate the second security key (S1) in a payload of the PDCCH signal. In some aspects, the PDCCH signal may schedule a PDSCH signal.

As shown inFIG.10, in some aspects, process1000may include receiving a PDSCH signal indicating a third security key (e.g., S2) (block1030). For example, the UE (e.g., using communication manager140and/or reception component1102, depicted inFIG.11) may receive a PDSCH signal indicating a third security key (e.g., S2), as described above. The PDSCH signal may indicate the third security key in a payload of the PDSCH signal. In some aspects, the PDSCH signal may be scheduled by the PDCCH signal.

As shown inFIG.10, in some aspects, process1000may include determining whether the PDSCH signal is authenticated (block1040). For example, the UE (e.g., using communication manager140and/or signal authentication component1108, depicted inFIG.11) may determine whether the PDSCH signal is authenticated, as described above. For example, the UE may authenticate the PDSCH signal based at least in part on the first security key, the second security key, and the third security key.

In some aspects, the UE may generate, using an authentication function, an authentication key (e.g., ƒa( )) based at least in part on the first security key and the second security key. The UE120may determine whether the PDSCH signal is authenticated based at least in part on whether the authentication key matches the third security key (e.g., whether S2=ƒa(S1, S3)).

As shown inFIG.10, in some aspects, if the UE determines that the PDSCH signal is authenticated, then process1000may include enabling communications with a device that transmitted the PDSCH signal (block1050). For example, the UE (e.g., using communication manager140and/or signal authentication component1108, depicted inFIG.11) may enable communications with a device that transmitted the PDSCH signal, as described above.

As shown inFIG.10, in some aspects, if the UE determines that the PDSCH signal is not authenticated, then process1000may include blocking communications with a device that transmitted the PDSCH signal (block1060). For example, the UE (e.g., using communication manager140and/or signal authentication component1108, depicted inFIG.11) may block communications with a device that transmitted the PDSCH signal, as described above. For example, the UE may prevent or refrain from receiving future communications from the device if the PDSCH signal is not authenticated.

The reception component1102may receive a first signal associated with a downlink control channel, wherein the first signal uses a modulation signature that identifies a first security key associated with an RIS, and wherein the first signal includes a second security key. The reception component1102may receive a second signal associated with a downlink shared channel, wherein the second signal includes a third security key, and wherein the second signal is authenticated by the UE based at least in part on the first security key, the second security key, and the third security key.

The signal authentication component1108may decode the second signal to authenticate the second signal using the first security key, the second security key, and the third security key. The signal authentication component1108may generate, using an authentication function, an authentication key based at least in part on the first security key and the second security key. The signal authentication component1108may authenticate the second signal based at least in part on whether the authentication key matches the third security key.

The transmission component1104may transmit, to a base station, a report for a link associated with the RIS, wherein the report indicates at least one of an identifier associated with the RIS and one or more measurements of one or more signals transmitted via the link, wherein the first signal using the modulation signature that identifies the first security key is based at least in part on the report.

The measurement component1110may measure the one or more signals transmitted via the link using an RIS reference signal associated with the one or more signals to obtain the one or more measurements.

The reception component1102may receive, from a base station, an indication of a fourth security key, wherein at least one of the second security key or the third security key is based at least in part on the fourth security key.

FIG.12is a diagram of an example apparatus1200for wireless communication. The apparatus1200may be a base station, or a base station may include the apparatus1200. In some aspects, the apparatus1200includes a reception component1202and a transmission component1204, which may be in communication with one another (for example, via one or more buses and/or one or more other components). As shown, the apparatus1200may communicate with another apparatus1206(such as a UE, a base station, or another wireless communication device) using the reception component1202and the transmission component1204. As further shown, the apparatus1200may include the communication manager150. The communication manager150may include a determination component1208, among other examples.

The transmission component1204may transmit, to an RIS, an indication of a first security key associated with the RIS, wherein the first security key is to be added, using a modulation signature, to signals reflected by the RIS. The transmission component1204may transmit a first signal that is associated with a downlink control channel, wherein the first signal includes a second security key, and wherein the first signal is to be reflected by the RIS. The transmission component1204may transmit a second signal that is associated with a downlink shared channel, wherein the second signal includes a third security key, and wherein the first security key, the second security key, and the third security key enable a UE to authenticate the second signal.

The reception component1202may receive, from the UE, a report for a link associated with the RIS, wherein the report indicates at least one of an identifier associated with the RIS and one or more measurements of one or more signals transmitted via the link, and wherein transmitting, to the RIS, the indication of the first security key is based at least in part on the report.

The determination component1208may identify a link quality associated with the link based at least in part on the one or more measurements.

The determination component1208may determine whether the RIS is to use the first security key when redirecting or reflecting signals to the UE.

The transmission component1204may transmit, to the UE, an indication of a fourth security key, wherein at least one of the second security key or the third security key is based at least in part on the fourth security key.

FIG.13is a diagram of an example apparatus1300for wireless communication. The apparatus1300may be an RIS, or an RIS may include the apparatus1300. In some aspects, the apparatus1300includes a reception component1302and a transmission component1304, which may be in communication with one another (for example, via one or more buses and/or one or more other components). As shown, the apparatus1300may communicate with another apparatus1306(such as a UE, a base station, or another wireless communication device) using the reception component1302and the transmission component1304. As further shown, the apparatus1300may include the communication manager170. The communication manager170may include one or more of a redirection component1308, and/or a modulation component1310, among other examples.

The reception component1302may receive, from a base station, an indication of a first security key associated with the RIS, wherein the first security key is to be added, using a modulation signature, to signals reflected by the RIS. The reception component1302may receive, from the base station, a first signal associated with a downlink control channel, wherein the first signal includes a second security key. The redirection component1308may redirect, to a UE, the first signal by including the modulation signature that identifies the first security key in the first signal. The redirection component1308may redirect, to the UE, a second signal, wherein the second signal includes a third security key, and wherein the first security key, the second security key, and the third security key enable the UE to authenticate the second signal.

The modulation component1310may modulate the first signal in phase, polarization state, and/or amplitude in accordance with the modulation signature to insert the first security key into the first signal.

Aspect 1: A method of wireless communication performed by a user equipment (UE), comprising: receiving a first signal associated with a downlink control channel, wherein the first signal uses a modulation signature that identifies a first security key associated with a reconfigurable intelligent surface (RIS), and wherein the first signal includes a second security key; and receiving a second signal associated with a downlink shared channel, wherein the second signal includes a third security key, and wherein the second signal is authenticated by the UE based at least in part on the first security key, the second security key, and the third security key.

Aspect 2: The method of Aspect 1, further comprising: decoding the second signal to authenticate the second signal using the first security key, the second security key, and the third security key.

Aspect 3: The method of any of Aspects 1-2, wherein decoding the second signal to authenticate the second signal comprises: generating, using an authentication function, an authentication key based at least in part on the first security key and the second security key; and authenticating the second signal based at least in part on whether the authentication key matches the third security key.

Aspect 4: The method of any of Aspects 1-3, further comprising: transmitting, to a base station, a report for a link associated with the RIS, wherein the report indicates at least one of an identifier associated with the RIS and one or more measurements of one or more signals transmitted via the link, wherein the first signal using the modulation signature that identifies the first security key is based at least in part on the report.

Aspect 5: The method of Aspect 4, further comprising: measuring the one or more signals transmitted via the link using an RIS reference signal associated with the one or more signals to obtain the one or more measurements.

Aspect 6: The method of any of Aspects 4-5, wherein the first signal using the modulation signature that identifies the first security key is based at least in part on the one or more measurements satisfying a threshold.

Aspect 7: The method of any of Aspects 4-6, wherein the report includes an indication of whether the one or more measurements satisfy a threshold, and wherein the first signal using the modulation signature that identifies the first security key is based at least in part on whether the one or more measurements satisfy the threshold.

Aspect 8: The method of any of Aspects 1-7, wherein the modulation signature is at least one of a phase modulation signature, a polarization modulation signature, or an amplitude modulation signature.

Aspect 9: The method of any of Aspects 1-8, wherein the first security key is based at least in part on an identifier associated with the RIS.

Aspect 10: The method of any of Aspects 1-9, wherein the modulation signature further identifies an identifier associated with the RIS.

Aspect 11: The method of any of Aspects 1-10, further comprising: receiving, from a base station, an indication of a fourth security key, wherein at least one of the second security key or the third security key is based at least in part on the fourth security key.

Aspect 12: The method of Aspect 11, wherein receiving the indication of the fourth security key comprises: receiving, from the base station, the indication of the fourth security key as part of a connection establishment procedure with the base station.

Aspect 13: The method of any of Aspects 11-12, wherein the fourth security key is associated with at least one of UE-specific data security or medium access control signaling security.

Aspect 14: The method of any of Aspects 1-13, wherein the first signal using the modulation signature that identifies the first security key is based at least in part on the first signal being associated with a beam state or a spatial direction that is associated with the UE.

Aspect 15: A method of wireless communication performed by a base station, comprising: transmitting, to a reconfigurable intelligent surface (RIS), an indication of a first security key associated with the RIS, wherein the first security key is to be added, using a modulation signature, to signals reflected by the RIS; transmitting a first signal that is associated with a downlink control channel, wherein the first signal includes a second security key, and wherein the first signal is to be reflected by the RIS; and transmitting a second signal that is associated with a downlink shared channel, wherein the second signal includes a third security key, and wherein the first security key, the second security key, and the third security key enable a user equipment (UE) to authenticate the second signal.

Aspect 16: The method of Aspect 15, further comprising: receiving, from the UE, a report for a link associated with the RIS, wherein the report indicates at least one of an identifier associated with the RIS and one or more measurements of one or more signals transmitted via the link, and wherein transmitting, to the RIS, the indication of the first security key is based at least in part on the report.

Aspect 17: The method of Aspect 16, further comprising: identifying a link quality associated with the link based at least in part on the one or more measurements.

Aspect 18: The method of any of Aspects 16-17, wherein transmitting, to the RIS, the indication of the first security key is based at least in part on the one or more measurements satisfying a threshold.

Aspect 19: The method of any of Aspects 16-18, wherein the report includes an indication of whether the one or more measurements satisfy a threshold, and wherein transmitting, to the RIS, the indication of the first security key is based at least in part on whether the one or more measurements satisfy the threshold.

Aspect 20: The method of any of Aspects 15-19, wherein the modulation signature is at least one of a phase modulation signature, a polarization modulation signature, or an amplitude modulation signature.

Aspect 21: The method of any of Aspects 15-20, wherein the first security key is based at least in part on an identifier associated with the RIS.

Aspect 22: The method of any of Aspects 15-21, further comprising: transmitting, to the UE, an indication of a fourth security key, wherein at least one of the second security key or the third security key is based at least in part on the fourth security key.

Aspect 23: The method of Aspect 22, wherein transmitting the indication of the fourth security key comprises: transmitting, to the UE, the indication of the fourth security key as part of a connection establishment procedure with the UE.

Aspect 24: The method of any of Aspects 22-23, wherein the fourth security key is associated with at least one of UE-specific data security or medium access control signaling security.

Aspect 25: The method of any of Aspects 15-24, wherein transmitting, to the RIS, the indication of the first security key comprises: transmitting an indication of a beam state or a spatial direction to which the first security key is to be added by the RIS.

Aspect 26: A method of wireless communication performed by a reconfigurable intelligent surface (RIS), comprising: receiving, from a base station, an indication of a first security key associated with the RIS, wherein the first security key is to be added, using a modulation signature, to signals reflected by the RIS; receiving, from the base station, a first signal associated with a downlink control channel, wherein the first signal includes a second security key; redirecting, to a user equipment (UE), the first signal by including the modulation signature that identifies the first security key in the first signal; and redirecting, to the UE, a second signal, wherein the second signal includes a third security key, and wherein the first security key, the second security key, and the third security key enable the UE to authenticate the second signal.

Aspect 27: The method of Aspect 26, wherein the modulation signature is at least one of a phase modulation signature, a polarization modulation signature, or an amplitude modulation signature.

Aspect 28: The method of any of Aspects 26-27, wherein the modulation signature is a polarization modulation signature, and wherein redirecting the first signal comprises: modulating a polarization state of the first signal from a first polarization state of the first signal as transmitted by the base station to a second polarization state of the first signal, wherein the polarization state includes an angle of polarization or a polarization mode.

Aspect 29: The method of any of Aspects 26-28, wherein the modulation signature identifies the first security key and an identifier associated with the RIS.

Aspect 30: The method of any of Aspects 26-29, wherein the first security key is based at least in part on an identifier associated with the RIS.

Aspect 31: The method of any of Aspects 26-30, wherein at least one of the second security key or the third security key is based at least in part on a fourth security key.

Aspect 32: The method of Aspect 31, wherein the fourth security key is established as part on a connection establishment procedure between the base station and the UE.

Aspect 33: The method of any of Aspects 26-32, wherein redirecting the first signal including the modulation signature is based at least in part on a quality of a link between the RIS and the UE satisfying a threshold.

Aspect 34: The method of any of Aspects 26-33, wherein receiving the indication of the first security key comprises: receiving an indication of a beam state or a spatial direction to which the first security key is to be added by the RIS; and wherein redirecting the first signal by including the modulation signature that identifies the first security key in the first signal is based at least in part on the first signal being redirected using the beam state or the spatial direction.