Millimeter wave (mmwave) discovery in sub 7 gigahertz frequency band

Abstract

One approach comprises a method in a wireless device, WD (22), configured to communicate with a network node (16), the WD (22) including a first radio front end (83) and a second radio front end (83), the first radio front end (83) operating in a first frequency band, and the second radio front end (83) operating in a second frequency band that is higher than the first frequency band. The method comprises receiving (S142) a first signal in the first frequency band by the first radio front end (83); estimating (S144) a first link budget for the first signal; predicting (S146) a second link budget for communication in the second frequency band by the second radio front end (83) based at least in part on the estimated first link budget; and communicating (S148) on the second frequency band based at least in part on the second link budget. In other approaches, the WD (22) gets more support from a network node.

Description

[0001] MILLIMETER WAVE (MMWAVE) DISCOVERY IN SUB 7 GIGAHERTZ FREQUENCY BAND

[0002] TECHNICAL FIELD

[0003] The present disclosure relates to wireless communications, and in particular, to millimeter wave (mmWave) discovery in a sub-7 GHz frequency band.

[0004] BACKGROUND

[0005] The Third Generation Partnership Project (3GPP) has developed and is developing standards for Fourth Generation (4G) (also referred to as Long Term Evolution (LTE)) and Fifth Generation (5G) (also referred to as New Radio (NR)) wireless communication systems. Such systems provide, among other features, broadband communication between network nodes, such as base stations, and mobile wireless devices (WD), as well as communication between network nodes and between WDs. The 3GPP is also developing standards for Sixth Generation (6G) wireless communication networks.

[0006] In addition to these standards, the Institute of Electrical and Electronic Engineers (IEEE) has developed and continues to develop standards for other types of wireless communication networks, including Wireless Local Area Networks (WLANs), including Wireless Fidelity (Wi-Fi) networks and Bluetooth networks. WLANs include wireless communication between access points (APs) and non-AP stations (STAs). Such IEEE standards may include IEEE 802.1 la / b / g / n / ac / ax and IEEE 802.15.

[0007] Discovery in sub 7 GHz

[0008] To enable discovery of and synchronization to an 802.11 network, an access point (AP) periodically transmits a beacon frame on its primary 20 MHz channel, with a beacon time interval that is typically set to 102.4 ms. The beacon is an omnidirectional transmission that allows a station (STA) to discover the network. A STA that receives the beacon may discover both the capabilities of this basic service set (BSS) and estimate its received signal strength indicator (RS SI) to the AP, which lets the STA rank the BSS compared to other BSSs it already knows about, in order to select the best AP to connect to. After having discovered the network, a STA may send an Association Request Frame in order to establish a connection.

[0009] Beacons must be transmitted using carrier sense multiple access with collision avoidance (CSMA / CA) and thus, if the medium is busy at the intended time of the beacon transmission, the AP must defer its beacon transmission until it gets access to the wireless medium, as may be seen in FIG. 1. FIG. 1 shows beacon transmission on a busy network. Discovery in IEEE 802, 1 lad / 1 lay

[0010] In IEEE 8021 lad, a procedure was introduced that divides the transmissions in between each beacon (called a beacon interval (BI)) into 3 separate phases. These phases are:

[0011] • Beacon Transmission Interval (BTI);

[0012] • Association Beamforming Training (A-BFT); and

[0013] • Data Transmission Interval (DTI).

[0014] The first two phases which are used in order to discover and associate a new STA to the AP are discussed. These three phases are shown in FIG. 2.

[0015] At the start of every BTI, the AP schedules an initiator transmit sector sweep (TXSS) to transmit beacons through all sectors. The AP may also fragment the TXSS across multiple beacon intervals if the BTI is insufficient and cannot complete the TXSS. A STA uses an omnidirectional receiving antenna configuration to scan nonassociated beacons or receive associated beacons from the AP and determine the best sector / antenna ID using the sector sweep field at the end of the TXSS.

[0016] If multiple transmit antennas are supported, an AP cannot switch its transmit antennas for beacon transmissions within a BTI, nor may it transmit a beacon more than once using the same antenna configuration. The AP changes the order of sectors across beacon intervals if multiple directional beacon transmissions are required or waits for a random delay at the start of beacon interval if only a single beacon is to be transmitted.

[0017] The AP announces the existence of an A-BFT period in the beacons, and this information is used for association and beamforming training for new STAs that join the network. A-BFT may not be present in each beacon interval and may be periodically inserted by the AP. The A-BFT period allows STAs to perform responder sector sweep (RSS) and sector sweep feedback (SSW-FB) phases of beamforming with the AP. The A-BFT period is a slotted phase where each slot is a multiple of the time required for RSS and SSW-FB. The new STAs use random backoff to select the A-BFT slot for an RSS. There may be no chance to do RSS during A-BFT because STAs use random access; therefore, the AP may schedule an SP to continue beamforming with the particular station.

[0018] Positioning

[0019] In 2015, the Next Generation Positioning Study Group started its activity to address the need of a station to identify its absolute and relative position to another station or stations. Draft 7.0 was made available in September 2022 and at this point, only editorial comments remain to be resolved. One main purpose with this amendment is to extend the Fine Time Measurement (FTM), to enable better accuracy in determination of absolute and relative positioning, as well as enabling passive positioning.

[0020] The fine time measurement (FTM) protocol may be used to estimate time of flight (ToF). FTM was first presented in IEEE 802.1 Imc. In the FTM protocol, the ToF is used to estimate the distance between two nodes. The distance may then be used by several nodes to estimate the position of one node using triangulation. The FTM exchange protocol may be initiated by any STA.

[0021] SUMMARY

[0022] The disclosure is based on the understanding that large path loss is present at mmWave bands, and high directionality transmissions are generally required at mmWave frequencies for communication to be possible. That means that e.g., beacons in mmWave band should be sent directionally in order to properly estimate if a connection may be made since an omni-directional beacon would have very limited range. But due to the narrow beams, a beam sweeping scheme, where a beacon is sent in each beam, may be time consuming and inefficient. This disclosure proposes approaches for alleviating these drawbacks.

[0023] Some embodiments advantageously provide methods, systems, and apparatuses for millimeter wave (mmWave) discovery in a sub-7 GHz frequency band.

[0024] A procedure is disclosed for a non-AP multi-link device (MLD) with one link in sub 7 GHz and one in mmWave to discover and estimate the link quality in the mmWave link using the sub 7 GHz link.

[0025] A procedure is disclosed for a first MLD with one link in sub 7 GHz and one link in mmWave to use the sub 7 GHz link in order to discover and estimate if a connection with a second MLD in a mmWave channel is possible.

[0026] By applying methods disclosed herein, unnecessary sectorized beacon transmissions in the mmWave band may be avoided to reduce overhead and thus, increase capacity. By relying on sub-7GHz non beamformed transmissions, a faster estimation of the mmWave transmission quality can be done. Moreover, mmWave control information may also be transmitted on the lower bands.

[0027] According to one aspect, in some embodiments, a method in a wireless device, WD, configured to communicate with a network node is provided. The WD includes a first radio front end and a second radio front end, the first radio front end operating in a first frequency band, and the second radio front end operating in a second frequency band that is higher than the first frequency band. The method includes receiving a first signal in the first frequency band by the first radio front end; estimating a first link budget for the first signal; predicting a second link budget for communication in the second frequency band by the second radio front end based at least in part on the estimated first link budget; and communicating on the second frequency band based at least in part on the second link budget.

[0028] According to this aspect, in some embodiments, the first link budget estimation is based at least in part on a received power of the first signal and a transmit power of the first signal. In some embodiments, the first link budget estimation is further based at least in part on a distance between the network node and the WD. In some embodiments, the method includes determining whether the network node is in a line of sight of the WD based at least in part on the first link budget estimation. In some embodiments, the second link-budget estimation is further based at least in part on transmit parameters associated with the second frequency band. In some embodiments, the transmit parameters for the second link are received in a frame of the first signal. In some embodiments, a frame of the first signal, transmitted in the first link, includes a first part that is transmitted at a first power level and a second part that is transmitted at a second power level that is lower than the first power level. In some embodiments, a difference between the first power level and the second power level is selected to mimic the difference in propagation conditions of the first frequency band and the second frequency band. In some embodiments, the method includes omitting communication in the second frequency band when the predicted second link budget does not exceed a first threshold. In some embodiments, the first threshold is based at least in part on at least one of a signal to noise ratio, SNR, and a modulation and coding scheme, MCS, of a set of supported MCSs.

[0029] According to another aspect, a method in a wireless device, WD, configured to communicate with a network node is provided. The WD includes a first radio front end and a second radio front end, the first radio front end operating in a first frequency band, and the second radio front end operating in a second frequency band that is higher than the first frequency band. The method includes: receiving a first signal in the first frequency band by the first radio front end; estimating a first link budget for the first signal; reporting the estimated first link budget to the network node; receiving information about operating communication on the second frequency band; and communicating on the second frequency band based at least in part on the received information.

[0030] According to this aspect, in some embodiments, the estimated first link budget is further based at least in part on a distance between the network node and the WD. In some embodiments, the method includes determining whether the network node is in a line of sight of the WD based at least in part on the first link budget for the first signal. In some embodiments, the first link budget estimation is based at least in part on a received power of the first signal and a transmit power of the first signal. In some embodiments, the operating communication on the second frequency band comprises omitting communication on the second frequency band when the second link budget does not reach a first threshold. In some embodiments, a frame of the first signal, transmitted in the first link, includes a first part that is transmitted at a first power level and a second part that is transmitted at a second power level that is lower than the first power level. In some embodiments, a difference between the first power level and the second power level is selected to mimic the difference in propagation conditions of the first frequency band and the second frequency band.

[0031] According to yet another aspect, a method in a wireless device, WD, configured to communicate with a network node is provided. The WD includes a first radio front end and a second radio front end, the first radio front end operating in a first frequency band, and the second radio front end operating in a second frequency band that is higher than the first frequency band. The method includes: receiving a first signal in the first frequency band by the first radio front end; estimating a first link budget for the first signal; predicting a second link budget for communication in the second frequency band by the second radio front end based at least in part on the estimated first link budget; reporting the predicted second link budget to the network node; receiving information about operating communication on the second frequency band; and communicating on the second frequency band based at least in part on the received information. According to this aspect, in some embodiments, the second link budget estimation is further based at least in part on transmit parameters associated with the second frequency band. In some embodiments, the transmit parameters are received in a frame of the first signal. In some embodiments, a frame of the first signal includes a first part that is transmitted at a first power level that is higher than a second power level of transmission of a second part of the frame. In some embodiments, a difference between the first power level and the second power level is selected to mimic the difference in propagation conditions of the first frequency band and the second frequency band. In some embodiments, the first link budget estimation is based at least in part on a received power of the first signal and a transmit power of the first signal. In some embodiments, the first link budget estimation is further based at least in part on a distance between the network node and the WD. In some embodiments, the method includes determining whether the network node is in a line of sight of the WD based at least in part on the first link budget estimation.

[0032] According to another aspect, a WD, configured to communicate with a network node is provided. The WD includes a radio interface comprising: a first radio front end and a second radio front end, the first radio front end operating in a first frequency band and configured to receive a first signal in the first frequency band; and a second radio front end operating in a second frequency band that is higher than the first frequency band. The WD includes processing circuitry in communication with the radio interface and configured to: estimate a first link budget for the first signal; and predict a second link budget for communication in the second frequency band by the second radio front end based at least in part on the estimated first link budget, wherein the radio interface is configured to communicate on the second frequency band based at least in part on the second link budget.

[0033] According to this aspect, in some embodiments, the first link budget estimation is based at least in part on a received power of the first signal and a transmit power of the first signal. In some embodiments, the first link budget estimation is further based at least in part on a distance between the network node and the WD. In some embodiments, the processing circuitry is configured to determine whether the network node is in a line of sight of the WD based at least in part on the first link budget estimation. In some embodiments, the second link-budget estimation is further based at least in part on transmit parameters associated with the second frequency band. In some embodiments, the transmit parameters for the second link are received in a frame of the first signal. In some embodiments, a frame of the first signal includes a first part that is transmitted at a first power level and a second part that is transmitted at a second power level that is lower than the first power level. In some embodiments, a difference between the first power level and the second power level is selected to mimic the difference in propagation conditions of the first frequency band and the second frequency band. In some embodiments, configured to omit communication in the second frequency band when the predicted second link budget does not exceed a first threshold. In some embodiments, the first threshold is based at least in part on at least one of a signal to noise ratio, SNR, and a modulation and coding scheme, MCS, of a set of supported MCSs.

[0034] According to yet another aspect, a wireless device, WD, configured to communicate with a network node is provided. The WD including a first radio front end and a second radio front end, the first radio front end operating in a first frequency band, and the second radio front end operating in a second frequency band that is higher than the first frequency band. The WD includes a radio interface configured to receive a first signal in the first frequency band by the first radio front end. The WD includes processing circuitry in communication with the radio interface and configured to estimate a first link budget for the first signal. The radio interface is further configured to report the estimated first link budget to the network node and receive information about operating communication on the second frequency band; and to communicate on the second frequency band based at least in part on the received information.

[0035] According to this aspect, in some embodiments, the first link budget estimation is based at least in part on a received power of the first signal and a transmit power of the first signal. In some embodiments, the estimated first link budget is further based at least in part on a distance between the network node and the WD. In some embodiments, the processing circuitry is further configured to determine whether the network node is in a line of sight of the WD based at least in part on the first link budget for the first signal. In some embodiments, the radio interface is configured to omit communication on the second frequency band when the second link budget does not reach a first threshold. In some embodiments, a frame of the first signal, transmitted in the first link, includes a first part that is transmitted at a first power level and a second part that is transmitted at a second power level that is lower than the first power level. In some embodiments, a difference between the first power level and the second power level is selected to mimic the difference in propagation conditions of the first frequency band and the second frequency band.

[0036] According to another aspect, a wireless device, WD, configured to communicate with a network node is provided. The WD includes a radio interface comprising: a first radio front end and a second radio front end, the first radio front end operating in a first frequency band and configured to receive a first signal in the first frequency band; and a second radio front end operating in a second frequency band that is higher than the first frequency band. The WD includes processing circuitry in communication with the radio interface and configured to: estimate a first link budget for the first signal; and predict a second link budget for communication in the second frequency band by the second radio front end based at least in part on the estimated first link budget. The radio interface is configured to: report the predicted second link budget to the network node; receive information about operating communication on the second frequency band; and communicate on the second frequency band based at least in part on the received information.

[0037] According to this aspect, in some embodiments, the second link budget estimation is further based at least in part on transmit parameters associated with the second frequency band. In some embodiments, the transmit parameters are received in a frame of the signal. In some embodiments, the frame of the signal includes a first part that is transmitted at a first power level that is higher than a second power level of transmission of a second part of the frame. In some embodiments, a difference between the first power level and the second power level is selected to mimic the difference in propagation conditions of the first frequency band and the second frequency band. In some embodiments, the first link budget estimation is based at least in part on a received power of the first signal and a transmit power of the first signal. In some embodiments, the first link budget estimation is further based at least in part on a distance between the network node and the WD. In some embodiments, the WD is further configured to determine whether the network node is in a line of sight of the WD based at least in part on the first link budget estimation.

[0038] According to yet another aspect, a method in a network node configured to communicate with a wireless device, WD is provided. The WD includes a first radio front end and a second radio front end, the first radio front end operating in a first frequency band, and the second radio front end operating in a second frequency band that is higher than the first frequency band. The method includes: transmitting a first signal in the first frequency band; receiving from the WD a first link budget estimate, the first link budget estimate being based at least in part on a received power of the first signal and a transmit power of the first signal; predicting a second link budget for communication in the second frequency band based at least in part on the first link budget estimate; and transmitting to the WD information about operating communication on the second frequency band, wherein the information is based at least in part on the second link budget.

[0039] According to this aspect, in some embodiments, the second link budget estimation is based at least in part on transmit parameters associated with the second frequency band. In some embodiments, a frame of the first signal includes a first part that is transmitted at a first power level and a second part that is transmitted at a second power level that is lower than the first power level. In some embodiments, a difference between the first power level and the second power level is selected to mimic the difference in propagation conditions of the first frequency band and the second frequency band. In some embodiments, the method includes omitting communication in the second frequency band when a predicted second link budget does not exceed a first threshold. In some embodiments, the first threshold is based at least in part on at least one of a signal to noise ratio, SNR, and a modulation and coding scheme, MCS, of a set of supported MCSs.

[0040] According to another aspect, a network node configured to communicate with a wireless device, WD is provided. The network node includes a radio interface configured to: transmit a first signal in a first frequency band; and receive from the WD a first link budget estimate, the first link budget estimate being based at least in part on a received power of the first signal and a transmit power of the first signal. The network node includes processing circuitry in communication with the radio interface and configured to predict a second link budget for communication in the second frequency band based at least in part on the first link budget estimate. The radio interface is further configured to transmit to the WD information about operating communication on the second frequency band, wherein the information is based at least in part on the second link budget.

[0041] According to this aspect, in some embodiments, the second link budget estimation is based at least in part on transmit parameters associated with the second frequency band. In some embodiments, a frame of the first signal includes a first part that is transmitted at a first power level and a second part that is transmitted at a second power level that is lower than the first power level. In some embodiments, a difference between the first power level and the second power level is selected to mimic the difference in propagation conditions of the first frequency band and the second frequency band. In some embodiments, the processing circuitry is configured to omit communication in the second frequency band when a predicted second link budget does not exceed a first threshold. In some embodiments, the first threshold is based at least in part on at least one of a signal to noise ratio, SNR, and a modulation and coding scheme, MCS, of a set of supported MCSs.

[0042] BRIEF DESCRIPTION OF THE DRAWINGS

[0043] A more complete understanding of the present embodiments, and the attendant advantages and features thereof, will be more readily understood by reference to the following detailed description when considered in conjunction with the accompanying drawings wherein:

[0044] FIG. 1 illustrates beacon transmissions in successive beacon intervals;

[0045] FIG. 2 illustrates a transmission procedure within a beacon interval;

[0046] FIG. 3 is a schematic diagram of an example network architecture illustrating a communication system connected via an intermediate network to a host computer according to the principles in the present disclosure;

[0047] FIG. 4 is a block diagram of a host computer communicating via a network node with a wireless device over an at least partially wireless connection according to some embodiments of the present disclosure;

[0048] FIG. 5 is a flowchart illustrating example methods implemented in a communication system including a host computer, a network node and a wireless device for executing a client application at a wireless device according to some embodiments of the present disclosure;

[0049] FIG. 6 is a flowchart illustrating example methods implemented in a communication system including a host computer, a network node and a wireless device for receiving user data at a wireless device according to some embodiments of the present disclosure;

[0050] FIG. 7 is a flowchart illustrating example methods implemented in a communication system including a host computer, a network node and a wireless device for receiving user data from the wireless device at a host computer according to some embodiments of the present disclosure;

[0051] FIG. 8 is a flowchart illustrating example methods implemented in a communication system including a host computer, a network node and a wireless device for receiving user data at a host computer according to some embodiments of the present disclosure;

[0052] FIG. 9 is a flowchart of an example process in a network node for millimeter wave (mmWave) discovery in a sub-7 GHz frequency band;

[0053] FIG. 10 is a flowchart of an example process in a wireless device for millimeter wave (mmWave) discovery in a sub-7 GHz frequency band;

[0054] FIG. 11 is a flowchart of another example process in a wireless device for millimeter wave (mmWave) discovery in a sub-7 GHz frequency band;

[0055] FIG. 12 is a flowchart of another example process in a wireless device according to some embodiments of the present disclosure;

[0056] FIG. 13 is an example scenario where a non-AP MLD performs estimation when a mmWave link may be established based on a transmission by an AP MLD;

[0057] FIG. 14 is an example variant for a UHR sub 7 GHz beacon;

[0058] FIG. 15 is another example variant for a UHR sub 7 GHz beacon;

[0059] FIG. 16 is an example exchange of messages on a sub 7 GHz channel;

[0060] FIG. 17 is an example of ranging coupled with a path loss model to estimate LOS / NLOS conditions; and

[0061] FIG. 18 is an example for connecting to a 60 GHz link for test transmission to determine estimation correctness.

[0062] DETAILED DESCRIPTION

[0063] Before describing in detail example embodiments, it is noted that the embodiments reside primarily in combinations of apparatus components and processing steps related to millimeter wave (mmWave) discovery in a sub-7 GHz frequency band. Accordingly, components have been represented where appropriate by conventional symbols in the drawings, showing only those specific details that are pertinent to understanding the embodiments so as not to obscure the disclosure with details that will be readily apparent to those of ordinary skill in the art having the benefit of the description herein. Like numbers refer to like elements throughout the description.

[0064] As used herein, relational terms, such as “first” and “second,” “top” and “bottom,” and the like, may be used solely to distinguish one entity or element from another entity or element without necessarily requiring or implying any physical or logical relationship or order between such entities or elements. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the concepts described herein. As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises,” “comprising,” “includes” and / or “including” when used herein, specify the presence of stated features, integers, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof.

[0065] In embodiments described herein, the joining term, “in communication with” and the like, may be used to indicate electrical or data communication, which may be accomplished by physical contact, induction, electromagnetic radiation, radio signaling, infrared signaling or optical signaling, for example. One having ordinary skill in the art will appreciate that multiple components may interoperate and modifications and variations are possible of achieving the electrical and data communication.

[0066] In some embodiments described herein, the term “coupled,” “connected,” and the like, may be used herein to indicate a connection, although not necessarily directly, and may include wired and / or wireless connections.

[0067] The term “network node” used herein may be any kind of network node included in a radio network which may further include any of base station (BS), radio base station, base transceiver station (BTS), base station controller (BSC), radio network controller (RNC), g Node B (gNB), evolved Node B (eNB or eNodeB), Node B, access point (AP), multi-standard radio (MSR) radio node such as MSR BS, multi-cell / multicast coordination entity (MCE), integrated access and backhaul (IAB) node, relay node, donor node controlling relay, radio access point (AP), transmission points, transmission nodes, Remote Radio Unit (RRU) Remote Radio Head (RRH), a core network node (e.g., mobile management entity (MME), self-organizing network (SON) node, a coordinating node, positioning node, MDT node, etc.), an external node (e.g., 3rdparty node, a node external to the current network), nodes in distributed antenna system (DAS), a spectrum access system (SAS) node, an element management system (EMS), etc. The network node may also include test equipment. The term “radio node” used herein may be used to also denote a wireless device (WD) or a radio network node.

[0068] In some embodiments, the non-limiting terms wireless device (WD) or a user equipment (UE) are used interchangeably. A WD may also refer to a station (STA) or a non-access point station (non-AP STA). The WD herein may be any type of wireless device capable of communicating with a network node or another WD over radio signals, such as wireless device (WD). The WD may also be a radio communication device, target device, device to device (D2D) WD, machine type WD or WD capable of machine to machine communication (M2M), low-cost and / or low-complexity WD, a sensor equipped with WD, Tablet, mobile terminals, smart phone, laptop embedded equipped (LEE), laptop mounted equipment (LME), USB dongles, Customer Premises Equipment (CPE), an Internet of Things (loT) device, or a Narrowband loT (NB-IOT) device, etc.

[0069] Also, in some embodiments the generic term “radio network node” is used. It may be any kind of a radio network node which may include any of an AP, base station, radio base station, base transceiver station, base station controller, network controller, RNC, evolved Node B (eNB), Node B, gNB, Multi-cell / multicast Coordination Entity (MCE), IAB node, relay node, access point, radio access point, Remote Radio Unit (RRU) Remote Radio Head (RRH).

[0070] Note that although terminology from one particular wireless system, such as, for example, Wi-Fi, IEEE 802.11, 3GPP LTE and / or New Radio (NR), may be used in this disclosure, this should not be seen as limiting the scope of the disclosure to only the aforementioned system. Other wireless systems, including without limitation Wide Band Code Division Multiple Access (WCDMA), Worldwide Interoperability for Microwave Access (WiMax), Ultra Mobile Broadband (UMB) and Global System for Mobile Communications (GSM), may also benefit from exploiting the ideas covered within this disclosure.

[0071] Note further, that functions described herein as being performed by a wireless device or a network node may be distributed over a plurality of wireless devices and / or network nodes. In other words, it is contemplated that the functions of the network node and wireless device described herein are not limited to performance by a single physical device and, in fact, may be distributed among several physical devices.

[0072] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. It will be further understood that terms used herein should be interpreted as having a meaning that is consistent with their meaning in the context of this specification and the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

[0073] Some embodiments provide millimeter wave (mmWave) discovery in a sub-7 GHz frequency range.

[0074] Returning now to the drawing figures, in which like elements are referred to by like reference numerals, there is shown in FIG. 3 a schematic diagram of a communication system 10, according to an embodiment, such as an IEEE 802.11 -type wireless communication system or a 3 GPP -type cellular network that may support standards such as LTE and / or NR (5G). The communication system 10 includes an access network 12, such as a radio access network, and a core network 14. The access network 12 includes a plurality of network nodes 16a, 16b, 16c (referred to collectively as network nodes 16), such as APS, NBs, eNBs, gNBs or other types of wireless access points, each defining a corresponding coverage area 18a, 18b, 18c (referred to collectively as coverage areas 18). Each network node 16a, 16b, 16c is connectable to the core network 14 over a wired or wireless connection 20. A first non-AP station or wireless device (WD) 22a located in coverage area 18a is configured to wirelessly connect to, or be paged by, the corresponding AP or network node 16a. A second non-AP station or WD 22b in coverage area 18b is wirelessly connectable to the corresponding AP or network node 16b. Herein, the terms wireless device and non-AP station shall be used interchangeably. The terms network node and AP or AP STA shall be used interchangeably. While a plurality of WDs 22a, 22b (collectively referred to as wireless devices 22) are illustrated in this example, the disclosed embodiments are equally applicable to a situation where a sole WD is in the coverage area or where a sole WD is connecting to the corresponding network node 16. Note that although only two WDs 22 and three network nodes 16 are shown for convenience, the communication system may include many more WDs 22 and network nodes 16.

[0075] Also, it is contemplated that a WD 22 may be in simultaneous communication and / or configured to separately communicate with more than one network node 16 and more than one type of network node 16. For example, a WD 22 may have dual connectivity with a network node 16 that supports LTE and the same or a different network node 16 that supports NR. As an example, WD 22 may be in communication with an eNB for LTE / E-UTRAN and a gNB for NR / NG-RAN.

[0076] The communication system 10 may itself be connected to a host computer 24, which may be embodied in the hardware and / or software of a standalone server, a cloud- implemented server, a distributed server or as processing resources in a server farm. The host computer 24 may be under the ownership or control of a service provider, or may be operated by the service provider or on behalf of the service provider. The connections 26, 28 between the communication system 10 and the host computer 24 may extend directly from the core network 14 to the host computer 24 or may extend via an optional intermediate network 30. The intermediate network 30 may be one of, or a combination of more than one of, a public, private or hosted network. The intermediate network 30, if any, may be a backbone network or the Internet. In some embodiments, the intermediate network 30 may include two or more sub-networks (not shown).

[0077] The communication system of FIG. 3 as a whole enables connectivity between one of the connected WDs 22a, 22b and the host computer 24. The connectivity may be described as an over-the-top (OTT) connection. The host computer 24 and the connected WDs 22a, 22b are configured to communicate data and / or signaling via the OTT connection, using the access network 12, the core network 14, any intermediate network 30 and possible further infrastructure (not shown) as intermediaries. The OTT connection may be transparent in the sense that at least some of the participating communication devices through which the OTT connection passes are unaware of routing of uplink and downlink communications. For example, a network node 16 may not or need not be informed about the past routing of an incoming downlink communication with data originating from a host computer 24 to be forwarded (e.g., handed over) to a connected WD 22a. Similarly, the network node 16 need not be aware of the future routing of an outgoing uplink communication originating from the WD 22a towards the host computer 24.

[0078] A network node 16 is configured to include a network node feasibility unit 32 which is configured to one of determine and receive a feasibility of operation in a second frequency band based at least in part on first link budget estimation, the first link budget estimation being based at least in part on a received power of the first signal and a transmit power of the first signal. A wireless device 22 is configured to include a WD feasibility unit 34 which is configured to determine a feasibility of operation in the second frequency band based at least in part on a predicted second link budget.

[0079] Example implementations, in accordance with an embodiment, of the WD 22, network node 16 and host computer 24 discussed in the preceding paragraphs will now be described with reference to FIG. 4. In a communication system 10, a host computer 24 includes hardware (HW) 38 including a communication interface 40 configured to set up and maintain a wired or wireless connection with an interface of a different communication device of the communication system 10. The host computer 24 further includes processing circuitry 42, which may have storage and / or processing capabilities. The processing circuitry 42 may include a processor 44 and memory 46. In particular, in addition to or instead of a processor, such as a central processing unit, and memory, the processing circuitry 42 may include integrated circuitry for processing and / or control, e.g., one or more processors and / or processor cores and / or FPGAs (Field Programmable Gate Array) and / or ASICs (Application Specific Integrated Circuitry) adapted to execute instructions. The processor 44 may be configured to access (e.g., write to and / or read from) memory 46, which may include any kind of volatile and / or nonvolatile memory, e.g., cache and / or buffer memory and / or RAM (Random Access Memory) and / or ROM (Read-Only Memory) and / or optical memory and / or EPROM (Erasable Programmable Read-Only Memory).

[0080] Processing circuitry 42 may be configured to control any of the methods and / or processes described herein and / or to cause such methods, and / or processes to be performed, e.g., by host computer 24. Processor 44 corresponds to one or more processors 44 for performing host computer 24 functions described herein. The host computer 24 includes memory 46 that is configured to store data, programmatic software code and / or other information described herein. In some embodiments, the software 48 and / or the host application 50 may include instructions that, when executed by the processor 44 and / or processing circuitry 42, causes the processor 44 and / or processing circuitry 42 to perform the processes described herein with respect to host computer 24. The instructions may be software associated with the host computer 24.

[0081] The software 48 may be executable by the processing circuitry 42. The software 48 includes a host application 50. The host application 50 may be operable to provide a service to a remote user, such as a WD 22 connecting via an OTT connection 52 terminating at the WD 22 and the host computer 24. In providing the service to the remote user, the host application 50 may provide user data which is transmitted using the OTT connection 52. The “user data” may be data and information described herein as implementing the described functionality. In one embodiment, the host computer 24 may be configured for providing control and functionality to a service provider and may be operated by the service provider or on behalf of the service provider. The processing circuitry 42 of the host computer 24 may enable the host computer 24 to observe, monitor, control, transmit to and / or receive from the network node 16 and or the wireless device 22.

[0082] The communication system 10 further includes a network node 16 provided in a communication system 10 and including hardware 58 enabling it to communicate with the host computer 24 and with the WD 22. The hardware 58 may include a communication interface 60 for setting up and maintaining a wired or wireless connection with an interface of a different communication device of the communication system 10, as well as a radio interface 62 for setting up and maintaining at least a wireless connection 64 with a WD 22 located in a coverage area 18 served by the network node 16. The radio interface 62 may be formed as or may include, for example, one or more RF transmitters, one or more RF receivers, and / or one or more RF transceivers. The communication interface 60 may be configured to facilitate a connection 66 to the host computer 24. The connection 66 may be direct or it may pass through a core network 14 of the communication system 10 and / or through one or more intermediate networks 30 outside the communication system 10.

[0083] In the embodiment shown, the hardware 58 of the network node 16 further includes processing circuitry 68. The processing circuitry 68 may include a processor 70 and a memory 72. In particular, in addition to or instead of a processor, such as a central processing unit, and memory, the processing circuitry 68 may include integrated circuitry for processing and / or control, e.g., one or more processors and / or processor cores and / or FPGAs (Field Programmable Gate Array) and / or ASICs (Application Specific Integrated Circuitry) adapted to execute instructions. The processor 70 may be configured to access (e.g., write to and / or read from) the memory 72, which may include any kind of volatile and / or nonvolatile memory, e.g., cache and / or buffer memory and / or RAM (Random Access Memory) and / or ROM (Read-Only Memory) and / or optical memory and / or EPROM (Erasable Programmable Read-Only Memory).

[0084] Thus, the network node 16 further has software 74 stored internally in, for example, memory 72, or stored in external memory (e.g., database, storage array, network storage device, etc.) accessible by the network node 16 via an external connection. The software 74 may be executable by the processing circuitry 68. The processing circuitry 68 may be configured to control any of the methods and / or processes described herein and / or to cause such methods, and / or processes to be performed, e.g., by network node 16. Processor 70 corresponds to one or more processors 70 for performing network node 16 functions described herein. The memory 72 is configured to store data, programmatic software code and / or other information described herein. In some embodiments, the software 74 may include instructions that, when executed by the processor 70 and / or processing circuitry 68, causes the processor 70 and / or processing circuitry 68 to perform the processes described herein with respect to network node 16. For example, processing circuitry 68 of the network node 16 may include a network node feasibility unit 32 which is configured to one of determine and receive a feasibility of operation in a second frequency band based at least in part on first link budget estimation, the first link budget estimation being based at least in part on a received power of the first signal and a transmit power of the first signal.

[0085] The communication system 10 further includes the WD 22 already referred to. The WD 22 may have hardware 80 that may include a radio interface 82 configured to set up and maintain a wireless connection 64 with a network node 16 serving a coverage area 18 in which the WD 22 is currently located. The radio interface 82 may be formed as or may include, for example, one or more RF transmitters, one or more RF receivers, and / or one or more RF transceivers. In particular, the radio interface 82 includes a plurality of radio front ends 83 configured to receive and / or transmit signals in two different frequency bands.

[0086] The hardware 80 of the WD 22 further includes processing circuitry 84. The processing circuitry 84 may include a processor 86 and memory 88. In particular, in addition to or instead of a processor, such as a central processing unit, and memory, the processing circuitry 84 may include integrated circuitry for processing and / or control, e.g., one or more processors and / or processor cores and / or FPGAs (Field Programmable Gate Array) and / or ASICs (Application Specific Integrated Circuitry) adapted to execute instructions. The processor 86 may be configured to access (e.g., write to and / or read from) memory 88, which may include any kind of volatile and / or nonvolatile memory, e.g., cache and / or buffer memory and / or RAM (Random Access Memory) and / or ROM (Read-Only Memory) and / or optical memory and / or EPROM (Erasable Programmable Read-Only Memory).

[0087] Thus, the WD 22 may further include software 90, which is stored in, for example, memory 88 at the WD 22, or stored in external memory (e.g., database, storage array, network storage device, etc.) accessible by the WD 22. The software 90 may be executable by the processing circuitry 84. The software 90 may include a client application 92. The client application 92 may be operable to provide a service to a human or non-human user via the WD 22, with the support of the host computer 24. In the host computer 24, an executing host application 50 may communicate with the executing client application 92 via the OTT connection 52 terminating at the WD 22 and the host computer 24. In providing the service to the user, the client application 92 may receive request data from the host application 50 and provide user data in response to the request data. The OTT connection 52 may transfer both the request data and the user data. The client application 92 may interact with the user to generate the user data that it provides. The processing circuitry 84 may be configured to control any of the methods and / or processes described herein and / or to cause such methods, and / or processes to be performed, e.g., by WD 22. The processor 86 corresponds to one or more processors 86 for performing WD 22 functions described herein. The WD 22 includes memory 88 that is configured to store data, programmatic software code and / or other information described herein. In some embodiments, the software 90 and / or the client application 92 may include instructions that, when executed by the processor 86 and / or processing circuitry 84, causes the processor 86 and / or processing circuitry 84 to perform the processes described herein with respect to WD 22. For example, the processing circuitry 84 of the wireless device 22 may include a WD feasibility unit 34 which is configured to determine a feasibility of operation in the second frequency band based at least in part on a predicted second link budget.

[0088] In FIG. 4, the OTT connection 52 has been drawn abstractly to illustrate the communication between the host computer 24 and the wireless device 22 via the network node 16, without explicit reference to any intermediary devices and the precise routing of messages via these devices. Network infrastructure may determine the routing, which it may be configured to hide from the WD 22 or from the service provider operating the host computer 24, or both. While the OTT connection 52 is active, the network infrastructure may further take decisions by which it dynamically changes the routing (e.g., on the basis of load balancing consideration or reconfiguration of the network).

[0089] The wireless connection 64 between the WD 22 and the network node 16 is in accordance with the teachings of the embodiments described throughout this disclosure. One or more of the various embodiments improve the performance of OTT services provided to the WD 22 using the OTT connection 52, in which the wireless connection 64 may form the last segment. More precisely, the teachings of some of these embodiments may improve the data rate, latency, and / or power consumption and thereby provide benefits such as reduced user waiting time, relaxed restriction on file size, better responsiveness, extended battery lifetime, etc.

[0090] In some embodiments, a measurement procedure may be provided for the purpose of monitoring data rate, latency and other factors on which the one or more embodiments improve. There may further be an optional network functionality for reconfiguring the OTT connection 52 between the host computer 24 and WD 22, in response to variations in the measurement results. The measurement procedure and / or the network functionality for reconfiguring the OTT connection 52 may be implemented in the software 48 of the host computer 24 or in the software 90 of the WD 22, or both. In embodiments, sensors (not shown) may be deployed in or in association with communication devices through which the OTT connection 52 passes; the sensors may participate in the measurement procedure by supplying values of the monitored quantities exemplified above, or supplying values of other physical quantities from which software 48, 90 may compute or estimate the monitored quantities. The reconfiguring of the OTT connection 52 may include message format, retransmission settings, preferred routing etc.; the reconfiguring need not affect the network node 16, and it may be unknown or imperceptible to the network node 16. Some such procedures and functionalities may be known and practiced in the art. In certain embodiments, measurements may involve proprietary WD signaling facilitating the host computer’s 24 measurements of throughput, propagation times, latency and the like. In some embodiments, the measurements may be implemented in that the software 48, 90 causes messages to be transmitted, in particular empty or ‘dummy’ messages, using the OTT connection 52 while it monitors propagation times, errors, etc.

[0091] Thus, in some embodiments, the host computer 24 includes processing circuitry 42 configured to provide user data and a communication interface 40 that is configured to forward the user data to a cellular network for transmission to the WD 22. In some embodiments, the cellular network also includes the network node 16 with a radio interface 62. In some embodiments, the network node 16 is configured to, and / or the network node’s 16 processing circuitry 68 is configured to perform the functions and / or methods described herein for preparing / initiating / maintaining / supporting / ending a transmission to the WD 22, and / or preparing / terminating / maintaining / supporting / ending in receipt of a transmission from the WD 22.

[0092] In some embodiments, the host computer 24 includes processing circuitry 42 and a communication interface 40 that is configured to a communication interface 40 configured to receive user data originating from a transmission from a WD 22 to a network node 16. In some embodiments, the WD 22 is configured to, and / or includes a radio interface 82 and / or processing circuitry 84 configured to perform the functions and / or methods described herein for preparing / initiating / maintaining / supporting / ending a transmission to the network node 16, and / or preparing / terminating / maintaining / supporting / ending in receipt of a transmission from the network node 16.

[0093] Although FIGS. 3 and 4 show various “units” such as NN feasibility unit 32, and WD feasibility unit 34 as being within a respective processor, it is contemplated that these units may be implemented such that a portion of the unit is stored in a corresponding memory within the processing circuitry. In other words, the units may be implemented in hardware or in a combination of hardware and software within the processing circuitry.

[0094] FIG. 5 is a flowchart illustrating an example method implemented in a communication system, such as, for example, the communication system of FIGS. 3 and 4, in accordance with one embodiment. The communication system may include a host computer 24, a network node 16 and a WD 22, which may be those described with reference to FIG. 4. In a first step of the method, the host computer 24 provides user data (Block SI 00). In an optional substep of the first step, the host computer 24 provides the user data by executing a host application, such as, for example, the host application 50 (Block SI 02). In a second step, the host computer 24 initiates a transmission carrying the user data to the WD 22 (Block SI 04). In an optional third step, the network node 16 transmits to the WD 22 the user data which was carried in the transmission that the host computer 24 initiated, in accordance with the teachings of the embodiments described throughout this disclosure (Block SI 06). In an optional fourth step, the WD 22 executes a client application, such as, for example, the client application 92, associated with the host application 50 executed by the host computer 24 (Block SI 08).

[0095] FIG. 6 is a flowchart illustrating an example method implemented in a communication system, such as, for example, the communication system of FIG. 3, in accordance with one embodiment. The communication system may include a host computer 24, a network node 16 and a WD 22, which may be those described with reference to FIGS. 3 and 4. In a first step of the method, the host computer 24 provides user data (Block SI 10). In an optional substep (not shown) the host computer 24 provides the user data by executing a host application, such as, for example, the host application 50. In a second step, the host computer 24 initiates a transmission carrying the user data to the WD 22 (Block SI 12). The transmission may pass via the network node 16, in accordance with the teachings of the embodiments described throughout this disclosure. In an optional third step, the WD 22 receives the user data carried in the transmission (Block SI 14).

[0096] FIG. 7 is a flowchart illustrating an example method implemented in a communication system, such as, for example, the communication system of FIG. 3, in accordance with one embodiment. The communication system may include a host computer 24, a network node 16 and a WD 22, which may be those described with reference to FIGS. 3 and 4. In an optional first step of the method, the WD 22 receives input data provided by the host computer 24 (Block SI 16). In an optional substep of the first step, the WD 22 executes the client application 92, which provides the user data in reaction to the received input data provided by the host computer 24 (Block SI 18). Additionally or alternatively, in an optional second step, the WD 22 provides user data (Block S120). In an optional substep of the second step, the WD provides the user data by executing a client application, such as, for example, client application 92 (Block S122). In providing the user data, the executed client application 92 may further consider user input received from the user. Regardless of the specific manner in which the user data was provided, the WD 22 may initiate, in an optional third substep, transmission of the user data to the host computer 24 (Block S124). In a fourth step of the method, the host computer 24 receives the user data transmitted from the WD 22, in accordance with the teachings of the embodiments described throughout this disclosure (Block S126).

[0097] FIG. 8 is a flowchart illustrating an example method implemented in a communication system, such as, for example, the communication system of FIG. 3, in accordance with one embodiment. The communication system may include a host computer 24, a network node 16 and a WD 22, which may be those described with reference to FIGS. 3 and 4. In an optional first step of the method, in accordance with the teachings of the embodiments described throughout this disclosure, the network node 16 receives user data from the WD 22 (Block S128). In an optional second step, the network node 16 initiates transmission of the received user data to the host computer 24 (Block SI 30). In a third step, the host computer 24 receives the user data carried in the transmission initiated by the network node 16 (Block SI 32).

[0098] FIG. 9 is a flowchart of an example process in a network node 16 for millimeter wave (mmWave) discovery in a sub-7 GHz frequency range. One or more blocks described herein may be performed by one or more elements of network node 16 such as by one or more of processing circuitry 68 (including the NN feasibility unit 32), processor 70, radio interface 62 and / or communication interface 60. Network node 16 such as via processing circuitry 68 and / or processor 70 and / or radio interface 62 and / or communication interface 60 is configured to transmit a first signal in the first frequency band (Block SI 34). The method includes receiving from the WD a first link budget estimate, the first link budget estimate being based at least in part on a received power of the first signal and a transmit power of the first signal (Block S136). The method includes determining a feasibility of operation in the second frequency band by predicting a communication quality for the second frequency band for providing a selection of a channel feasible for operation in the second frequency band (Block S138). The method includes transmitting to the WD the selection of the channel in the second frequency band for which the feasibility of communication is determined (Block S140).

[0099] In some embodiments, the second frequency band is a millimeter wave, mmWave, frequency band. In some embodiments, the feasibility of operation is determined by the network node and the received power of the first signal is reported to the network node by the WD 22. In some embodiments, determining the feasibility of operation in the second frequency band includes predicting a communication quality for the second frequency band. In some embodiments, the first link budget estimation is based at least in part on a distance between the network node and the WD 22. In some embodiments, the method includes determining whether the network node is in a line of sight of the WD 22 based at least in part on the first link budget estimation. In some embodiments, the second link budget estimation is based at least in part on transmit parameters associated with the second frequency band. In some embodiments, the transmit parameters are transmitted in a frame of the first signal. In some embodiments, the frame of the first signal includes a first part that is transmitted at a first power level and a second part that is transmitted at a second power level that is lower than the first power level. In some embodiments, determining the feasibility of operation in the second frequency band channel includes determining a link budget at a frequency in the second frequency band. In some embodiments, the method includes requesting the network node to transmit a beam in the second frequency band to enable the WD 22 to test the feasibility determination. In some embodiments, the first signal includes a first part having first frequency band beacon information transmitted at a first power level, a second part having second frequency band beacon information transmitted at the first power level, and a third part having mmWave related information transmitted at a second power level that is lower than the first power level. In some embodiments, a difference between the first power level and the second power level is selected to mimic different propagation conditions in the first frequency band and in the second frequency band. In some embodiments, the method includes transmitting to the WD 22 a selection of a channel in the second frequency band for which the feasibility of communication is determined. In some embodiments, the method includes, prior to transmitting the selection, transmitting to the WD 22 a trigger to cause the WD 22 to scan the second frequency band. In some embodiments, the method includes omitting communication in the second frequency band when a predicted second link budget does not exceed a first threshold. In some embodiments, the first threshold is based at least in part on at least one of a signal to noise ratio, SNR, and a modulation and coding scheme, MCS, of a set of supported MCSs.

[0100] FIG. 10 is a flowchart of an example process in a wireless device 22 according to some embodiments of the present disclosure. One or more blocks described herein may be performed by one or more elements of wireless device 22 such as by one or more of processing circuitry 84 (including the WD feasibility unit 34), processor 86, radio interface 82 and / or communication interface 60. Wireless device 22 such as via processing circuitry 84 and / or processor 86 and / or radio interface 82 is configured to receive (SI 42) a first signal in the first frequency band by the first radio front end; estimate (S144) a first link budget for the first signal; predict (S146) a second link budget for communication in the second frequency band by the second radio front end based at least in part on the estimated first link budget; and communicate (S148) on the second frequency band based at least in part on the second link budget.

[0101] According to this aspect, in some embodiments, the first link budget estimation is based at least in part on a received power of the first signal and a transmit power of the first signal. In some embodiments, the first link budget estimation is further based at least in part on a distance between the network node and the WD. In some embodiments, the method includes determining whether the network node is in a line of sight of the WD based at least in part on the first link budget estimation. In some embodiments, the second link-budget estimation is further based at least in part on transmit parameters associated with the second frequency band. In some embodiments, the transmit parameters for the second link are received in a frame of the first signal. In some embodiments, a frame of the first signal, transmitted in the first link, includes a first part that is transmitted at a first power level and a second part that is transmitted at a second power level that is lower than the first power level. In some embodiments, a difference between the first power level and the second power level is selected to mimic the difference in propagation conditions of the first frequency band and the second frequency band. In some embodiments, the method includes omitting communication in the second frequency band when the predicted second link budget does not exceed a first threshold. In some embodiments, the first threshold is based at least in part on at least one of a signal to noise ratio, SNR, and a modulation and coding scheme, MCS, of a set of supported MCSs.

[0102] FIG. 11 is a flowchart of an example process in a wireless device 22 according to some embodiments of the present disclosure. One or more blocks described herein may be performed by one or more elements of wireless device 22 such as by one or more of processing circuitry 84 (including the WD feasibility unit 34), processor 86, radio interface 82 and / or communication interface 60. Wireless device 22 such as via processing circuitry 84 and / or processor 86 and / or radio interface 82 is configured to receive (SI 50) a first signal in the first frequency band by the first radio front end; estimate (SI 52) a first link budget for the first signal; report (SI 54) the estimated first link budget to the network node; receive (SI 56) information about operating communication on the second frequency band; and communicate (SI 58) on the second frequency band based at least in part on the received information.

[0103] According to this aspect, in some embodiments, the estimated first link budget is further based at least in part on a distance between the network node and the WD. In some embodiments, the method includes determining whether the network node is in a line of sight of the WD based at least in part on the first link budget for the first signal. In some embodiments, the first link budget estimation is based at least in part on a received power of the first signal and a transmit power of the first signal. In some embodiments, the operating communication on the second frequency band comprises omitting communication on the second frequency band when the second link budget does not reach a first threshold. In some embodiments, a frame of the first signal, transmitted in the first link, includes a first part that is transmitted at a first power level and a second part that is transmitted at a second power level that is lower than the first power level. In some embodiments, a difference between the first power level and the second power level is selected to mimic the difference in propagation conditions of the first frequency band and the second frequency band.

[0104] FIG. 12 is a flowchart of another example process in a wireless device 22 according to some embodiments of the present disclosure. One or more blocks described herein may be performed by one or more elements of wireless device 22 such as by one or more of processing circuitry 84 (including the WD feasibility unit 34), processor 86, radio interface 82 and / or communication interface 60. Wireless device 22 such as via processing circuitry 84 and / or processor 86 and / or radio interface 82 is configured to receive (SI 60) a first signal in the first frequency band by the first radio front end; estimate (SI 62) a first link budget for the first signal; predict (SI 64) a second link budget for communication in the second frequency band by the second radio front end based at least in part on the estimated first link budget; report (SI 66) the predicted second link budget to the network node; receive (SI 68) information about operating communication on the second frequency band; and communicate (S170) on the second frequency band based at least in part on the received information.

[0105] According to this aspect, in some embodiments, the second link budget estimation is further based at least in part on transmit parameters associated with the second frequency band. In some embodiments, the transmit parameters are received in a frame of the first signal. In some embodiments, a frame of the first signal includes a first part that is transmitted at a first power level that is higher than a second power level of transmission of a second part of the frame. In some embodiments, a difference between the first power level and the second power level is selected to mimic the difference in propagation conditions of the first frequency band and the second frequency band. In some embodiments, the first link budget estimation is based at least in part on a received power of the first signal and a transmit power of the first signal. In some embodiments, the first link budget estimation is further based at least in part on a distance between the network node and the WD. In some embodiments, the method includes determining whether the network node is in a line of sight of the WD based at least in part on the first link budget estimation.

[0106] Having described the general process flow of arrangements of the disclosure and having provided examples of hardware and software arrangements for implementing the processes and functions of the disclosure, the sections below provide details and examples of arrangements for millimeter wave (mmWave) discovery in a sub-7 GHz frequency range.

[0107] General Description

[0108] According to one aspect, a non-AP MLD is configured to use the sub 7 GHz beacons to estimate if a connection may be established in a mmWave channel, or to estimate if an existing connection in a mmWave channel is suitable for communication. These estimations may be based on more than one sub 7 GHz beacon transmissions if the MLD has several sub 7 GHz links.

[0109] The estimations may be performed by, for example, one of the following:

[0110] • The non-AP MLD receives the sub 7GHz beacon, measures the RSSI (Received Signal Strength Indicator) and learns the mmWave capabilities of the AP MLD and calculates a mmWave link budget to estimate the feasibility of establishing / using a mmWave connection;

[0111] • The sub 7 GHz beacon may include a mmWave portion that advertises the availability of mmWave communication, but uses different Tx parameters on the mmWave portion to emulate the difference, e.g., in transmit power and / path loss, between the sub 7 GHz link and the mmWave link; and / or

[0112] • A non-AP MLD using FTM procedures, in the sub-7 GHz bands (or any other positioning technology not necessarily operating in the sub-7 GHz band), may get an estimate of its absolute position, or its relative position with respect to the serving AP MLD. A distance between the AP MLD and non-AP MLD is then calculated and by using proper transmit and link budget parameters in the mmWave band, an assessment may be made of the feasibility of connecting to or using an existing connection.

[0113] Some embodiments disclosed herein may be used not only by stationary non-AP MLDs but also mobile non-AP MLDs. In the stationary case, the estimations may not have to be performed as often if the relative positions or channel conditions with respect to all bands between the non-AP MLDs and the AP MLDs are somewhat constant. In the mobile case, the estimations may be performed often by a non-AP MLD to periodically track the quality of the mmWave link(s) - depending on the relative positions or channel conditions, the quality may remain similar, may improve, or may degrade.

[0114] Below are some examples and embodiments of these estimation techniques from the STA side, followed by some additional aspects one may apply at the AP side.

[0115] STA Initiated Discovery

[0116] Estimation Based on Packet Reception

[0117] In some embodiments, the non-AP MLD may make an estimation of the mmWave link quality based on some reference frame sent by the AP MLD in the lower band. This reference frame in the lower band may be, for example, a beacon frame or some new frame or element introduced for this purpose. The beacon frame may be used since it already contains transmit (Tx) configuration parameters and capabilities that may be essential to do a suitable estimation.

[0118] FIG. 13 is an example scenario where non-AP MLD 11 does estimation if a mmWave link may be established based on some transmission made by AP MLD 1.

[0119] In some embodiments, by assuming quasi-omnidirectional antenna patterns for the link budget calculation in the mmWave band, the non-AP MLD may use a worst-case scenario for the estimation and thus, by using beamforming techniques, the link budget should be able to improve by several dBs. As such, many of the false positives of non- line-of-sight (NLOS) non-AP MLDs that indicate they are in range might be salvaged by the beamforming gain. Although this comes at a cost, as some LOS non-AP MLDs that might be in range at mmWave frequencies will not set up their connection due to not taking the beamforming gain in the mmWave band into account and thus, resulting in false negatives.

[0120] As an example, a simple estimation of mmWave communication feasibility may be performed by the STA by measuring that the sub 7 GHz part of the beacon was received at an SINR of 30 dB. Suppose also that the transmit power is the same in both links, and it is announced in the beacon. Thus, by assuming a free space path loss model between 6 GHz and 60 GHz (which gives a loss of 20 additional dB) and the same gain by the respective antennas, the STA may calculate that the expected signal to interference plus noise ratio (SINR) in the mmWave channel should be around 10 dB. This may not be accurate and is meant to illustrate one example of how some embodiments may be employed. Complex estimation models may be employed that use other specific mmWave information or are based upon machine learning / artificial intelligence. Thus, the transmit parameters (which may be same or different for different links) that may be used to assess mmWave communication feasibility may comprise one or more of transmit power, bandwidth, MCS, operating channel, beamforming, etc.

[0121] Estimation Based on Discovery Frame

[0122] In some embodiments, the AP MLD when transmitting in the lower band makes a specific part of the lower-band beacon or a separate frame intentionally harder to decode than the legacy part of the beacon frame or another reference frame. It may do this by, for example:

[0123] • Changing the modulation and coding scheme (MCS) of the additional part;

[0124] • Lowering the transmit power on the additional part;

[0125] • Using a specific directionality, e.g., using specific signaling on request after having performed sub 7 GHz sounding; and / or

[0126] • A combination of the above.

[0127] FIG. 14 is variant for the UHR sub 7 GHz beacon. FIG. 14 shows an example, where the mmWave part of the beacon is attached to the sub 7 GHz part of the beacon and transmitted, for example, with lower power (represented by the height in the figure) than the sub 7 GHz related information.

[0128] The mmWave part may either be a part of the Sub 7 GHz beacon or it may be an independent frame, as shown in FIG. 14. As mentioned earlier, other modifications to the mmWave part are possible. Information carried in the mmWave Part may, for example, be the beacon information for the mmWave band. Another embodiment is depicted in FIG. 15. Here, the mmWave Part is as simple to decode as the Sub 7 GHz part. Thus, even if the mmWave link is poor, the non-AP STA may still receive the mmWave beacon information in the lower band. As shown, a separate discovery part may be introduced, in addition to the mmWave part, to act as an indicator of the quality of the mmWave link. The information in the discovery part may for example be a repetition of all, or parts, of the information in the mmWave Part, or information-less” data.

[0129] However, there exists a known issue with legacy STAs that start to operate improperly if they receive a beacon that is too large. Thus, in some embodiments, the mmWave part of the beacon may be an individual frame sent independently of the Sub 7 GHz Part.

[0130] One such example may be that the non-AP MLD first establishes a sub 7 GHz connection and reads in the lower band beacon that the AP MLD also has 60 GHz capabilities and then later asks the AP MLD to send a new 60 GHz discovery element in the lower band. This element may be used as explained above for estimation of the mmWave link. One such example is depicted in FIG. 16.

[0131] Similar to the example above, this would equate to the AP sending the mmWave part with 20 dB worse conditions compared to the sub 7 GHz beacon frame (or other reference frame) based on the free space pathloss model difference between sub 7 GHz and 60 GHz band, or alternatively the AP lowering the transmit power of the transmission. However, similar to that example, one may apply much more complex algorithms to model the pathloss difference between 6 and 60 GHz.

[0132] Estimation Based on Positioning

[0133] In some embodiments, the FTM positioning protocol introduced in IEEE 802.11 az amendment is leveraged in order to do an estimation of the feasibility of the 60 GHz connection. First the absolute STA position, or the relative position of the STA with respect to the AP is estimated. This may be done for example in the lower band where the AP’s coverage area is larger. Second, the STA determines for example how far it is from the AP (AP coordinates are carried in the beacon, they are needed when the STA knows only its absolute position). Finally, the STA may use a proper channel model for the 60 GHz band (including the transmit parameters for the 60 GHz band) and assess if it is out of range in the 60 GHz band.

[0134] In other cases, even if the distance STA-AP (computed in the lower band) is determined to be “small,” the received power may still be low in the sub-7 GHz band. In this case, the STA may infer that it is not in the line of sight (LOS) and apply a channel model for the 60 GHz. The STA may infer that it is out of coverage in the 60 GHz band even though the distance STA-AP may have supported a connection in LOS conditions.

[0135] One example may be seen in FIG. 17, where a STA that has used a ranging protocol in order to estimate its relative position to its AP and, based on a free space path loss model, has further estimated that it should receive transmissions with an average of 22 dB SINR, but measures that the average is only around 7 dB. Consequently, the STA draws the conclusion that it is not in LOS of the AP.

[0136] In other cases, if the received power in the sub-7GHz band is high, the non-AP STA by using proper channel models for the higher band and link budget parameters for the higher band may assess that a connection in the higher band may be established, and also get an estimate of the supported MCS in the higher band.

[0137] Note that STA may rely on other, i.e., non-IEEE technologies, for example, Global Positioning System (GPS), ultra- wide band (UWB), etc., to determine its position. Such technologies may operate in their own bands, i.e., not necessarily in the sub-7 GHz band. Similar as described above, once the STA position is determined it may be used in combination with lower band transmission to determine whether it is possible to have a successful transmission in a higher band.

[0138] Additional Embodiments

[0139] In some embodiments, the STA may trigger (in the lower band) the AP to send a message using a certain suggested beam in the mmWave link in order to see if the estimation on sub 7 GHz was correct before starting the data transfer. The transmitted message may either be a short packet, or a 60 GHz beacon etc. An example is shown in FIG. 18.

[0140] In some embodiments, one may use two or more of the techniques explained above to make a better estimation of the link quality in mmWave. For example, some embodiments determine a link budget in the sub 7 GHz for mmWave and also uses a positioning procedure to get an improved estimate of the link conditions.

[0141] In some embodiments, the STA does the estimation of the feasibility of communicating in a mmWave channel but then sends the report to the AP. This allows the AP to stay in control and manage which STAs should operate on which links at a given time without unnecessary attempts at mmWave communication that the AP would reject either way. The report may consist of a simple acknowledgement or contain further parameters such as expected RS SI, preferred beam or other related Tx information. AP Initiated Discovery

[0142] Because the AP has knowledge of both the downlink (DL) and uplink (UL) traffic requirements, the initialization of a link in the mmWave band may be performed by the AP, rather than the non-AP STA. Specifically, the AP may estimate the mmWave in a similar way as the STA would make such estimation, as disclosed above.

[0143] In some embodiments, once the AP decides that it is beneficial to use the mmWave band, the AP may request the STA(s) for which the AP intends to use the mmWave band to perform a scanning of the different channels in the mmWave band in order to find a suitable channel. A reason for performing this scanning may be to determine if a channel is severely interfered. Since the pathloss is high in the mmWave, the difference in experienced interference at the AP and at the STA may be pronounced and therefore it may not be possible for the AP to directly determine which one of the channels in the mmWave band would be suitable.

[0144] Once a suitable channel has been found in the mmWave band, this information may be shared with the STA and the AP may then initiate the usual channel set-up procedure including, for example, beam training. As the beam training may be a rather lengthy process, it is advantageous that the STA has identified that this a good channel to use, avoiding having to perform the beam training for more than one channel.

[0145] In some embodiments, the AP provides a minimum power to be received in the lower band that would allow for a successful connection in the higher band. Thus, only after meeting that requirement may a STA request or perform data transmissions in a mmWave channel.

[0146] Some additional aspects of some embodiments are provided as follows. Relevance of ‘Association’

[0147] In some of the examples above, assume 2 different cases for the association between an AP MLD and non-AP MLD. This may be dependent on what route is chosen, for example, in the UHR SG, for mmWave association and may alter what schemes are most probable or even feasible of the above-mentioned examples. Two cases are as follows:

[0148] Case 1 : A non-AP MLD and an AP MLD may set up sub-7 GHz as well as mmWave links together in already the first association related frame exchange between the two. To enable this, the AP MLD may include relevant information in the beacons such that the non-AP MLD may assess the possibility of setting up a mmWave link.

[0149] Case 2: A non-AP MLD and an AP MLD may first set up sub-7 GHz links in the first association related frame exchange, and then undertake additional frame exchanges to set up mmWave links. To enable this, the AP MLD might not include mmWave links related information already in the beacons, but may provide such information in separate frame exchanges, thereby avoiding issues such as beacon bloat as discussed earlier. FIG. 18 may thus correspond to Case 2 described here.

[0150] Case 1 above may be easier to specify than Case 2, since it may involve fewer or smaller changes to the already standardized multi-link association mechanisms. Moreover, for both cases 1 and 2 above, the mmWave links related information exchanges may be initiated either by the AP MLD or the non-AP MLD.

[0151] Mobility

[0152] The principles explained above may also be useful the cases when data is to be transmitted within a BSS. The estimation of communication feasibility may also be useful for making informed decisions to move from one BSS to another.

[0153] For example, a non-AP MLD that is connected to an AP MLD in the sub-7 GHz channels may overhear a beacon from a nearby AP MLD and estimate that the mmWave communication might be more beneficial with this AP MLD than its current AP MLD. This may be due to NLOS / LOS conditions and thus, the non-AP MLD may want to make the transition. This may help with initial beam training when performing the transitions, and data transmissions may be performed sooner. This may be useful for low latency services.

[0154] Some embodiments may include one or more of the following:

[0155] 1. The first MLD receiving one or more transmissions by a second MLD in a first link and based on those transmissions making an estimation if connectivity is viable in a second link, wherein the transmissions may be: a. A field of an available frame; b. An independent frame.

[0156] 2. As in embodiment 1, where the transmissions may be an identifiable reference frame, such as the beacon frame.

[0157] 3. As in embodiments 1-2, where the transmissions include transmission parameters for the second link.

[0158] 4. As in embodiment 3, where the transmission parameter is the transmitter power used in the second link

[0159] 5. As in embodiments 1-4 where the estimation is based on RSSI of, and capabilities advertised in, the beacon. 6. As in embodiments 1-4, where the estimation is based on a new signaling containing a Tx configuration that emulates the difference in channel conditions between the two links.

[0160] 7. As in embodiment 6, where the signaling is transmitted as a part of the sub 7 GHz beacon.

[0161] 8. As in embodiment 6, where the signaling is transmitted as a separate frame in order to limit beacon bloat.

[0162] 9. As in embodiment 1, where the transmissions in the lower bands are used for determining the position of the non-AP MLD.

[0163] 10. As in embodiment 9, where estimation is based on applying proper channel models and link budget models for the higher band.

[0164] 11. As in embodiment 1, where the transmission may be a feedback response containing parameters related to the estimation of the feasibility of a connection in the second link, such as, RS SI, preferred beam, etc.

[0165] 12. As in any of the above embodiments, where sounding on the first link is also used for estimation of the link quality.

[0166] 13. As in embodiment 12, where the STA informs the AP if the link is established by an acknowledgment type transmission on one or both of the links.

[0167] 14. As in any of the above embodiments, where the STA triggers the AP to send a transmission in the second link to find out if the estimation was correct

[0168] 15. As in any of the above embodiments, where the AP sends a signal strength limit the STA needs to estimate above before a connection attempt may be made.

[0169] 16. As in any of the above embodiments, where the first MLD is an AP and the second a STA where the AP asks the STA to scan the available channels in the second link to find which is most suitable.

[0170] 17. As in any of the above embodiments, where the first link is located in the sub 7 GHz band and the second link in a mmWave band.

[0171] As will be appreciated by one of skill in the art, the concepts described herein may be embodied as a method, data processing system, computer program product and / or computer storage media storing an executable computer program. Accordingly, the concepts described herein may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects all generally referred to herein as a “circuit” or “module.” Any process, step, action and / or functionality described herein may be performed by, and / or associated to, a corresponding module, which may be implemented in software and / or firmware and / or hardware. Furthermore, the disclosure may take the form of a computer program product on a tangible computer usable storage medium having computer program code embodied in the medium that may be executed by a computer. Any suitable tangible computer readable medium may be utilized including hard disks, CD-ROMs, electronic storage devices, optical storage devices, or magnetic storage devices.

[0172] Some embodiments are described herein with reference to flowchart illustrations and / or block diagrams of methods, systems and computer program products. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, may be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer (to thereby create a special purpose computer), special purpose computer, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions / acts specified in the flowchart and / or block diagram block or blocks.

[0173] These computer program instructions may also be stored in a computer readable memory or storage medium that may direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer readable memory produce an article of manufacture including instruction means which implement the function / act specified in the flowchart and / or block diagram block or blocks.

[0174] The computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions / acts specified in the flowchart and / or block diagram block or blocks.

[0175] It is to be understood that the functions / acts noted in the blocks may occur out of the order noted in the operational illustrations. For example, two blocks shown in succession may in fact be executed substantially concurrently or the blocks may sometimes be executed in the reverse order, depending upon the functionality / acts involved. Although some of the diagrams include arrows on communication paths to show a primary direction of communication, it is to be understood that communication may occur in the opposite direction to the depicted arrows.

[0176] Computer program code for carrying out operations of the concepts described herein may be written in an object oriented programming language such as Python, Java® or C++. However, the computer program code for carrying out operations of the disclosure may also be written in conventional procedural programming languages, such as the “C” programming language. The program code may execute entirely on the user’s computer, partly on the user’s computer, as a stand-alone software package, partly on the user’ s computer and partly on a remote computer or entirely on the remote computer. In the latter scenario, the remote computer may be connected to the user’s computer through a local area network (LAN) or a wide area network (WAN), or the connection may be made to an external computer (for example, through the Internet using an Internet Service Provider).

[0177] Many different embodiments have been disclosed herein, in connection with the above description and the drawings. It will be understood that it would be unduly repetitious and obfuscating to literally describe and illustrate every combination and subcombination of these embodiments. Accordingly, all embodiments may be combined in any way and / or combination, and the present specification, including the drawings, shall be construed to constitute a complete written description of all combinations and subcombinations of the embodiments described herein, and of the manner and process of making and using them, and shall support claims to any such combination or subcombination.

[0178] Abbreviations that may be used in the preceding description include: AP Access Point

[0179] BSS Basic Service Set

[0180] CSMA / CA Carrier Sense Multiple Access / Collision Avoidance FTM Fine Time Measurement

[0181] LOS Line Of Sight

[0182] MCS Modulation and Coding Scheme

[0183] MLD Multi-Link Device mmWave millimeter Wave NLOS Non-Line Of Sight

[0184] RS SI Received Signal Strength Indicator ST A Station

[0185] ToF Time of Flight

[0186] Tx Transmission

[0187] It will be appreciated by persons skilled in the art that the embodiments described herein are not limited to what has been particularly shown and described herein above. In addition, unless mention was made above to the contrary, it should be noted that all of the accompanying drawings are not to scale. A variety of modifications and variations are possible in light of the above teachings without departing from the scope of the following claims.

Claims

Claims:

1. A method in a wireless device, WD (22), configured to communicate with a network node (16), the WD (22) including a first radio front end (83) and a second radio front end (83), the first radio front end (83) operating in a first frequency band, and the second radio front end (83) operating in a second frequency band that is higher than the first frequency band, the method comprising: receiving (S142) a first signal in the first frequency band by the first radio front end (83); estimating (S144) a first link budget for the first signal; predicting (S146) a second link budget for communication in the second frequency band by the second radio front end (83) based at least in part on the estimated first link budget; and communicating (S148) on the second frequency band based at least in part on the second link budget.

2. The method of Claim 1, wherein the first link budget estimation is based at least in part on a received power of the first signal and a transmit power of the first signal.

3. The method of any of Claims 1-2, wherein the first link budget estimation is further based at least in part on a distance between the network node (16) and the WD (22).

4. The method of any of Claims 1-3, further comprising determining whether the network node (16) is in a line of sight of the WD (22) based at least in part on the first link budget estimation.

5. The method of any of Claims 1-4, wherein the second link-budget estimation is further based at least in part on transmit parameters associated with the second frequency band.

6. The method of Claim 5, wherein the transmit parameters for the second link are received in a frame of the first signal.

7. The method of any of Claims 1-6, wherein a frame of the first signal, transmitted in the first link, includes a first part that is transmitted at a first power level and a second part that is transmitted at a second power level that is lower than the first power level.

8. The method of Claim 7, wherein a difference between the first power level and the second power level is selected to mimic the difference in propagation conditions of the first frequency band and the second frequency band.

9. The method of any of Claims 1-8, further comprising omitting communication in the second frequency band when the predicted second link budget does not exceed a first threshold.

10. The method of Claim 9, wherein the first threshold is based at least in part on at least one of a signal to noise ratio, SNR, and a modulation and coding scheme, MCS, of a set of supported MCSs.

11. A method in a wireless device, WD (22), configured to communicate with a network node (16), the WD (22) including a first radio front end (83) and a second radio front end (83), the first radio front end (83) operating in a first frequency band, and the second radio front end (83) operating in a second frequency band that is higher than the first frequency band, the method comprising: receiving (SI 50) a first signal in the first frequency band by the first radio front end (83); estimating (SI 52) a first link budget for the first signal; reporting (SI 54) the estimated first link budget to the network node (16); receiving (SI 56) information about operating communication on the second frequency band; and communicating (SI 58) on the second frequency band based at least in part on the received information.

12. The method of Claim 11, wherein the estimated first link budget is further based at least in part on a distance between the network node (16) and the WD (22).

13. The method of any of Claims 11 and 12, further comprising determining whether the network node (16) is in a line of sight of the WD (22) based at least in part on the first link budget for the first signal.

14. The method of any of Claims 11-13, wherein the first link budget estimation is based at least in part on a received power of the first signal and a transmit power of the first signal.

15. The method of any of Claims 11-14, wherein the operating (SI 58) communication on the second frequency band comprises omitting communication on the second frequency band when the second link budget does not reach a first threshold.

16. The method of any of Claims 11-15, wherein a frame of the first signal, transmitted in the first link, includes a first part that is transmitted at a first power level and a second part that is transmitted at a second power level that is lower than the first power level.

17. The method of Claim 16, wherein a difference between the first power level and the second power level is selected to mimic the difference in propagation conditions of the first frequency band and the second frequency band.

18. A method in a wireless device, WD (22), configured to communicate with a network node (16), the WD (22) including a first radio front end (83) and a second radio front end (83), the first radio front end (83) operating in a first frequency band, and the second radio front end (83) operating in a second frequency band that is higher than the first frequency band, the method comprising: receiving (SI 60) a first signal in the first frequency band by the first radio front end (83); estimating (SI 62) a first link budget for the first signal; predicting (SI 64) a second link budget for communication in the second frequency band by the second radio front end (83) based at least in part on the estimated first link budget; reporting (SI 66) the predicted second link budget to the network node (16); receiving (SI 68) information about operating communication on the secondfrequency band; and communicating (SI 70) on the second frequency band based at least in part on the received information.

19. The method of Claim 18, wherein the second link budget estimation is further based at least in part on transmit parameters associated with the second frequency band.

20. The method of Claim 19, wherein the transmit parameters are received in a frame of the first signal.

21. The method of any one of Claims 18-20, wherein a frame of the first signal includes a first part that is transmitted at a first power level that is higher than a second power level of transmission of a second part of the frame.

22. The method of Claim 21, wherein a difference between the first power level and the second power level is selected to mimic the difference in propagation conditions of the first frequency band and the second frequency band.

23. The method of any of Claims 18-22, wherein the first link budget estimation is based at least in part on a received power of the first signal and a transmit power of the first signal.

24. The method of any of Claims 18-23, wherein the first link budget estimation is further based at least in part on a distance between the network node (16) and the WD (22).

25. The method of any of Claims 18-24, further comprising determining whether the network node (16) is in a line of sight of the WD (22) based at least in part on the first link budget estimation.

26. A wireless device, WD (22), configured to communicate with a network node (16), the WD (22) including: a radio interface (82) comprising:a first radio front end (83) and a second radio front end (83), the first radio front end (83) operating in a first frequency band and configured to receive a first signal in the first frequency band; and a second radio front end (83) operating in a second frequency band that is higher than the first frequency band; and processing circuitry (84) in communication with the radio interface (82) and configured to: estimate a first link budget for the first signal; and predict a second link budget for communication in the second frequency band by the second radio front end (83) based at least in part on the estimated first link budget, wherein the radio interface (82) is configured to communicate on the second frequency band based at least in part on the second link budget.

27. The WD (22) of Claim 26, wherein the first link budget estimation is based at least in part on a received power of the first signal and a transmit power of the first signal.

28. The WD (22) of any of Claims 26-27, wherein the first link budget estimation is further based at least in part on a distance between the network node (16) and the WD (22).

29. The WD (22) of any of Claims 26-28, wherein the processing circuitry (84) is configured to determine whether the network node (16) is in a line of sight of the WD (22) based at least in part on the first link budget estimation.

30. The WD (22) of any of Claims 26-29, wherein the second link-budget estimation is further based at least in part on transmit parameters associated with the second frequency band.

31. The WD (22) of Claim 30, wherein the transmit parameters for the second link are received in a frame of the first signal.

32. The WD (22) of any of Claims 26-31, wherein a frame of the first signalincludes a first part that is transmitted at a first power level and a second part that is transmitted at a second power level that is lower than the first power level.

33. The WD (22) of Claim 32 wherein a difference between the first power level and the second power level is selected to mimic the difference in propagation conditions of the first frequency band and the second frequency band.

34. The WD (22) of any of Claims 26-33, configured to omit communication in the second frequency band when the predicted second link budget does not exceed a first threshold.

35. The WD (22) of Claim 34, wherein the first threshold is based at least in part on at least one of a signal to noise ratio, SNR, and a modulation and coding scheme, MCS, of a set of supported MCSs.

36. A wireless device, WD (22), configured to communicate with a network node (16), the WD (22) including a first radio front end (83) and a second radio front end (83), the first radio front end (83) operating in a first frequency band, and the second radio front end (83) operating in a second frequency band that is higher than the first frequency band, the WD (22) comprising: a radio interface (82) configured to receive a first signal in the first frequency band by the first radio front end (83); processing circuitry (84) in communication with the radio interface (82) and configured to estimate a first link budget for the first signal; the radio interface (82) being further configured to report the estimated first link budget to the network node (16) and receive information about operating communication on the second frequency band; and the radio interface (82) is further configured to communicate on the second frequency band based at least in part on the received information.

37. The WD (22) of Claim 36, wherein the first link budget estimation is based at least in part on a received power of the first signal and a transmit power of the first signal.

38. The WD (22) of Claim 36 or 37, wherein the estimated first link budget is further based at least in part on a distance between the network node (16) and the WD (22).

39. The WD (22) of any of Claims 36-38, the processing circuitry (84) is further configured to determine whether the network node (16) is in a line of sight of the WD (22) based at least in part on the first link budget for the first signal.

40. The WD (22) of any of Claims 36-39, wherein the radio interface (82) is configured to omit communication on the second frequency band when the second link budget does not reach a first threshold.

41. The WD (22) of any of Claims 36-40, wherein a frame of the first signal, transmitted in the first link, includes a first part that is transmitted at a first power level and a second part that is transmitted at a second power level that is lower than the first power level.

42. The WD (22) of Claim 41, wherein a difference between the first power level and the second power level is selected to mimic the difference in propagation conditions of the first frequency band and the second frequency band.

43. A wireless device, WD (22), configured to communicate with a network node (16), the WD (22) including: a radio interface (82) comprising: a first radio front end (83) and a second radio front end (83), the first radio front end (83) operating in a first frequency band and configured to receive a first signal in the first frequency band; and a second radio front end (83) operating in a second frequency band that is higher than the first frequency band; and processing circuitry (84) in communication with the radio interface (82) and configured to: estimate a first link budget for the first signal; and predict a second link budget for communication in the second frequency band by the second radio front end (83) based at least in part on the estimated firstlink budget, the radio interface (82) being configured to: report the predicted second link budget to the network node; receive information about operating communication on the second frequency band; and communicate on the second frequency band based at least in part on the received information.

44. The WD (22) of Claim 43, wherein the second link budget estimation is further based at least in part on transmit parameters associated with the second frequency band.

45. The WD (22) of Claim 44, wherein the transmit parameters are received in a frame of the signal.

46. The WD (22) of any of Claims 43-45, wherein the frame of the signal includes a first part that is transmitted at a first power level that is higher than a second power level of transmission of a second part of the frame.

47. The WD (22) of Claim 46, wherein a difference between the first power level and the second power level is selected to mimic the difference in propagation conditions of the first frequency band and the second frequency band.

48. The WD (22) of any of Claims 43-47, wherein the first link budget estimation is based at least in part on a received power of the first signal and a transmit power of the first signal.

49. The WD (22) of any of Claims 43-48, wherein the first link budget estimation is further based at least in part on a distance between the network node (16) and the WD (22).

50. The WD (22) of any of Claims 43-49, further configured to determine whether the network node (16) is in a line of sight of the WD (22) based at least in part on the first link budget estimation.

51. A method in a network node (16) configured to communicate with a wireless device, WD (22), the WD (22) including a first radio front end (83) and a second radio front end (83), the first radio front end (83) operating in a first frequency band, and the second radio front end (83) operating in a second frequency band that is higher than the first frequency band, the method comprising: transmitting (SI 34) a first signal in the first frequency band; receiving (SI 36) from the WD (22) a first link budget estimate, the first link budget estimate being based at least in part on a received power of the first signal and a transmit power of the first signal; predicting (S146) a second link budget for communication in the second frequency band based at least in part on the first link budget estimate; and transmitting (SI 40) to the WD (22) information about operating communication on the second frequency band, wherein the information is based at least in part on the second link budget.

52. The method of Claim 51, wherein the second link budget estimation is based at least in part on transmit parameters associated with the second frequency band.

53. The method of any of Claims 51-52, wherein a frame of the first signal includes a first part that is transmitted at a first power level and a second part that is transmitted at a second power level that is lower than the first power level.

54. The method of Claim 53, wherein a difference between the first power level and the second power level is selected to mimic the difference in propagation conditions of the first frequency band and the second frequency band.

55. The method of any of Claims 51-54, further comprising omitting communication in the second frequency band when a predicted second link budget does not exceed a first threshold.

56. The method of Claim 55, wherein the first threshold is based at least in part on at least one of a signal to noise ratio, SNR, and a modulation and coding scheme, MCS, of a set of supported MCSs.

57. A network node (16) configured to communicate with a wireless device,WD (22), the network node (16) comprising: a radio interface (62) configured to: transmit a first signal in a first frequency band; and receive from the WD (22) a first link budget estimate, the first link budget estimate being based at least in part on a received power of the first signal and a transmit power of the first signal; and processing circuitry (68) in communication with the radio interface (62) and configured to predict a second link budget for communication in the second frequency band based at least in part on the first link budget estimate, the radio interface being further configured to transmit to the WD (22) information about operating communication on the second frequency band, wherein the information is based at least in part on the second link budget.

58. The network node (16) of Claim 57, wherein the second link budget estimation is based at least in part on transmit parameters associated with the second frequency band.

59. The network node (16) of any of Claims 57-58, wherein a frame of the first signal includes a first part that is transmitted at a first power level and a second part that is transmitted at a second power level that is lower than the first power level.

60. The network node (16) of Claim 59, wherein a difference between the first power level and the second power level is selected to mimic the difference in propagation conditions of the first frequency band and the second frequency band.

61. The network node (16) of any of Claims 57-60, wherein the processing circuitry (68) is configured to omit communication in the second frequency band when a predicted second link budget does not exceed a first threshold.

62. The network node (16) of Claim 61, wherein the first threshold is based at least in part on at least one of a signal to noise ratio, SNR, and a modulation and coding scheme, MCS, of a set of supported MCSs.

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