# US 2020/0404635 A1 · Apparatus and method for iot control channel > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2020/0404635 A1 - Document ID: US20200404635A1 - Status: Published application - Kind: A1 - Application number: 17/004,351 - Filed: 2020-08-27 - Published: 2020-12-24 - Earliest claimed: 2016-01-11 - Assignees: Apple Inc. - Applicants: Apple Inc. - Inventors: Ralf Matthias Bendlin; Debdeep Chatterjee; Seunghee Han - Web page: https://patentgrep.com/patent/US20200404635A1 ## CPC - H04W 72/23: in the downlink direction of a wireless link, i.e. towards a terminal - H04L 5/0053: {Allocation of signalling, i.e. of overhead other than pilot signals} - H04L 5/0007: {the frequencies being orthogonal, e.g. OFDM(A) or DMT} - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) ## Abstract Embodiments described herein include user equipment (UE), evolved node B (eNB), methods, and systems for narrowband Internet-of-Things (IoT) communications. Some embodiments particularly relate to control channel communications between UE and eNB in narrowband IoT communications. In one embodiment, a UE blind decodes a first control transmission from an evolved node B (eNB) by processing a first physical resource block comprising all subcarriers of the transmission bandwidth and all orthogonal frequency division multiplexed symbols of a first subframe to determine the first control transmission. In various further embodiments, various resource groupings of resource elements are used as part of the control communications. ## Claims ### Claim at position 1 -26. (canceled) ### Claim 27 An apparatus, comprising: a memory; and a processor in communication with the memory and arranged to cause a user equipment (UE) for narrowband internet-of-Things (NB-IoT) communication to: monitor signals on a first transmission bandwidth for a narrowband system with the first transmission bandwidth comprising a single physical resource block bandwidth; blind decode one or more narrowband physical downlink control channel (NB-PDCCH) search space candidates by processing a first physical resource block of the first transmission bandwidth and orthogonal frequency division multiplexed symbols of a first subframe, wherein said blind decoding comprises attempting to blind decode one or more NB-PDCCH search space candidates of a plurality of NB-PDCCH search space candidates, wherein each of the plurality of NB-PDCCH search space candidates are defined using a pair of an aggregation level (AL) and a repetition level (RL) to monitor, wherein the AL is defined as a number of narrowband control channel elements used within a subframe for NB-PDCCH transmission and the RL is defined as a number of subframes over which the narrowband control channel element(s) are repeated in a time dimension; and extract modulated symbols of a control channel transmission after successful blind decoding of a first NB-PDCCH search space candidate. ### Claim 28 (depends on 27) The apparatus of claim 27, wherein blind decoding the one or more NB-PDCCH search space candidates comprises processing a plurality of physical resource blocks, the plurality of physical resource blocks comprising the first physical resource block, wherein each physical resource block of the plurality of resource blocks comprises all subcarriers of the first transmission bandwidth for corresponding time periods. ### Claim 29 (depends on 28) The apparatus of claim 28, wherein the corresponding time periods for the plurality of physical resource blocks are consecutive in the time dimension. ### Claim 30 (depends on 28) The apparatus of claim 28, wherein the corresponding time periods for the plurality of physical resource blocks are not all consecutive in the time dimension. ### Claim 31 (depends on 28) The apparatus of claim 28, wherein the processor is further configured to cause the UE to extract modulated symbols of the one or more narrowband control channel elements of the control channel transmission according to the AL and the RL. ### Claim 32 (depends on 31) The apparatus of claim 31, wherein a subcarrier of one orthogonal frequency division multiplexed symbol comprises a resource element of a respective narrowband control channel element of the one or more narrowband control channel elements. ### Claim 33 (depends on 31) The apparatus of claim 31, wherein the respective narrowband control channel element comprises a first subcarrier of the first subframe. ### Claim 34 (depends on 33) The apparatus of claim 33, wherein the respective narrowband control channel element further comprises modulated symbols of the control channel transmission mapped to a direct current (DC) subcarrier of an orthogonal frequency division multiplexing (OFDM) waveform. ### Claim 35 (depends on 33) The apparatus of claim 33, wherein the respective narrowband control channel element comprises a set of subcarriers. ### Claim 36 (depends on 27) The apparatus of claim 27, wherein two narrowband control channel elements are defined within the subframe. ### Claim 37 (depends on 36) The apparatus of claim 36, wherein the AL is either 1 or 2 for the NB-PDCCH search space candidates. ### Claim 38 (depends on 37) The apparatus of claim 37, wherein a maximum of two NB-PDCCH transmissions are multiplexed in the subframe. ### Claim 39 (depends on 27) The apparatus of claim 27, further comprising: an antenna configured to receive the signals on the first transmission bandwidth and transmit the signals to the processor. ### Claim 40 A method for operating a user equipment (UE) for narrowband internet-of-Things (NB-IoT) communication, the method comprising: monitoring signals on a first transmission bandwidth for a narrowband system with the first transmission bandwidth comprising a single physical resource block bandwidth; blind decoding one or more narrowband physical downlink control channel (NB-PDCCH) search space candidates by processing a first physical resource block of the first transmission bandwidth and orthogonal frequency division multiplexed symbols of a first subframe, wherein said blind decoding comprises attempting to blind decode one or more NB-PDCCH search space candidates of a plurality of NB-PDCCH search space candidates, wherein each of the plurality of NB-PDCCH search space candidates are defined using a pair of an aggregation level (AL) and a repetition level (RL) to monitor, wherein the AL is defined as a number of narrowband control channel elements used within a subframe for NB-PDCCH transmission and the RL is defined as a number of subframes over which the narrowband control channel element(s) are repeated in a time dimension; and extracting modulated symbols of a control channel transmission after successful blind decoding of a first NB-PDCCH search space candidate. ### Claim 41 (depends on 40) The method of claim 40, wherein blind decoding the one or more NB-PDCCH search space candidates comprises processing a plurality of physical resource blocks, the plurality of physical resource blocks comprising the first physical resource block, wherein each physical resource block of the plurality of resource blocks comprises all subcarriers of the first transmission bandwidth for corresponding time periods. ### Claim 42 (depends on 41) The method of claim 41, the method further comprising: causing the UE to extract modulated symbols of one or more narrowband control channel elements of the control channel transmission according to the AL and the RL. ### Claim 43 An apparatus of a base station for encoding control channel signals for narrowband Internet-of-Things (NB-IoT) communications, the apparatus comprising: a memory; and a processor in communication with the memory and arranged to: encode a first control channel transmission using a first physical resource block of a first transmission bandwidth for a narrowband system and orthogonal frequency division multiplexed symbols of a first subframe; and transmit the first control channel transmission to a user equipment (UE) over a narrowband physical downlink control channel (NB-PDCCH), wherein the first control channel transmission comprises a first NB-PDCCH candidate for the UE to attempt to blind decode, wherein the NB-PDCCH candidate is selected from a plurality of NB-PDCCH candidates, wherein each of the plurality of NB-PDCCH search space candidates are defined using a pair of an aggregation level (AL) and a repetition level (RL) for monitoring, wherein the AL is defined as a number of narrowband control channel elements used within a subframe for the first control channel transmission and the RL is defined as a number of subframes over which the narrowband control channel element(s) are repeated in a time dimension. ### Claim 44 (depends on 43) The apparatus of claim 43, wherein the processor is further configured to encode the first control transmission from the base station to the UE using a plurality of physical resource blocks, the plurality of physical resource blocks comprising the first physical resource block, wherein each physical resource block of the plurality of resource blocks comprises all subcarriers of the first transmission bandwidth for corresponding time periods. ### Claim 45 (depends on 44) The apparatus of claim 44, wherein the corresponding time periods for the plurality of physical resource blocks are not all consecutive in the time domain. ### Claim 46 (depends on 43) The apparatus of claim 43, wherein two narrowband control channel elements are defined within the subframe.