# US 2014/0153659 A1 · Pilot design for universal frequency reuse in cellular orthogonal frequency-division multiplexing systems > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0153659 A1 - Document ID: US20140153659A1 - Status: Published application - Kind: A1 - Application number: 14/174,486 - Filed: 2014-02-06 - Published: 2014-06-05 - Earliest claimed: 2007-08-15 - Assignees: Marvell World Trade Ltd. - Applicants: Marvell World Trade Ltd. - Inventors: Jungwon Lee; Hui-Ling Lou - Web page: https://patentgrep.com/patent/US20140153659A1 ## CPC - H04L 25/03821: {Inter-carrier interference cancellation [ICI]} - H04L 5/0007: {the frequencies being orthogonal, e.g. OFDM(A) or DMT} - H04L 5/0039: {Frequency-contiguous, i.e. with no allocation of frequencies for one user or terminal between the frequencies allocated to another} - H04L 5/005: {of common pilots, i.e. pilots destined for multiple users or terminals} - H04L 5/0051: {of dedicated pilots, i.e. pilots destined for a single user or terminal} - H04L 5/0062: {Avoidance of ingress interference, e.g. ham radio channels} - H04L 5/0082: {at predetermined intervals} - H04L 5/0083: {symbol-by-symbol} - H04L 25/0204: {of multiple channels} - H04W 16/02: Resource partitioning among network components, e.g. reuse partitioning - H04L 5/0021: {in which codes are applied as a frequency-domain sequences, e.g. MC-CDMA} - H04L 25/0226: {sounding signals per se} - H04L 27/2613: {Structure of the reference signals} - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) ## Abstract Systems and methods are provided for transmitting information between an intended source and a receiver to minimize co-channel interference from at least one interfering source. Pilot subcarriers and data subcarriers may be broadcast from an intended source and at least one interfering source. The pilot subcarriers may be shared across base stations or distributed among base stations in frequency, in time, or both. In addition, the frequency reuse factor of the pilot subcarriers may be different than the frequency reuse factor of the data subcarriers A receiver receives a composite signal that corresponds with an intended signal from an intended source and an interfering signal from at least one interfering source. The portion of the received signal that corresponds to the intended signal may be recovered by the receiver based on the broadcast of the pilot subcarriers. ## Claims ### Claim at position 1 1-37. (canceled) ### Claim 38 A mobile device that recovers a first portion of a received signal associated with a first device, wherein the received signal comprises a second portion associated with a second device, the mobile device comprising: detection circuitry that detects a first pilot transmission associated with the first device during a first period of time, and a second pilot transmission associated with the second device during a second period of time that is different from the first period of time; an analyzer that determines a channel gain between the mobile device and the second device based on the second pilot transmission; and signal processing circuitry that recovers the first portion of the received signal based at least in part on the channel gain between the mobile device and the second device. ### Claim 39 (depends on 38) The mobile device of claim 38, wherein the detection circuitry detects the first pilot transmission and the second pilot transmission at a same frequency location. ### Claim 40 (depends on 39) The mobile device of claim 39, wherein the frequency location associated with the first pilot transmission and the second pilot transmission changes after a third period of time. ### Claim 41 (depends on 38) The mobile device of claim 38, wherein the second pilot transmission is associated with at least one subcarrier and the at least one subcarrier is unused by the first device during the second period of time. ### Claim 42 (depends on 38) The mobile device of claim 38, wherein at least one of the first pilot transmission and the second pilot transmission comprises a plurality of orthogonal sequences. ### Claim 43 (depends on 42) The mobile device of claim 42, wherein the plurality of orthogonal sequences corresponds to the columns of one of a Fourier matrix or a Hadamard matrix. ### Claim 44 (depends on 38) The mobile device of claim 38, wherein at least one of the first pilot transmission and the second pilot transmission comprises a pseudonoise code sequence. ### Claim 45 (depends on 38) The mobile device of claim 38, wherein the first pilot transmission and the second pilot transmission overlap by at least one subcarrier. ### Claim 46 (depends on 38) The mobile device of claim 38, wherein the detection circuitry is configured to: detect whether at least one of the first pilot transmission and the second pilot transmission is distributed over at least one of frequency and time. ### Claim 47 (depends on 38) The mobile device of claim 38, wherein the detection circuitry is configured to: detect whether at least a portion of the first pilot transmission and the second pilot transmission is shared between the first device and the second device. ### Claim 48 A method of recovering a first portion of a received signal associated with a first device, wherein the received signal comprises a second portion associated with a second device, the method comprising: detecting a first pilot transmission associated with the first device during a first period of time and a second pilot transmission associated with the second device during a second period of time that is different from the first period of time; analyzing the second pilot transmission to determine a channel gain between the mobile device and the second device; and recovering the first portion of the received signal based at least in part on the channel gain between the mobile device and the second device. ### Claim 49 (depends on 48) The method of claim 48, wherein detecting the first pilot transmission and the second pilot transmission comprises detecting the first pilot transmission and the second pilot transmission at a same frequency location. ### Claim 50 (depends on 49) The method of claim 49, wherein the frequency location associated with the first pilot transmission and the second pilot transmission changes after a third period of time. ### Claim 51 (depends on 48) The method of claim 48, wherein the second pilot transmission is associated with at least one pilot subcarrier and the at least one pilot subcarrier is unused by the first device during the second period of time. ### Claim 52 (depends on 48) The method of claim 48, wherein at least one of the first pilot transmission and the second pilot transmission comprises a plurality of orthogonal sequences. ### Claim 53 (depends on 52) The method of claim 52, wherein the plurality of orthogonal sequences corresponds to the columns of one of a Fourier matrix or a Hadamard matrix. ### Claim 54 (depends on 48) The method of claim 48, wherein at least one of the first pilot transmission and the second pilot transmission comprises a pseudonoise code sequence. ### Claim 55 (depends on 48) The method of claim 48, wherein the first pilot transmission and the second pilot transmission overlap by at least one subcarrier. ### Claim 56 (depends on 48) The method of claim 48, wherein detecting the first pilot transmission and the second pilot transmission comprises: detecting whether at least one of the first pilot transmission and the second pilot transmission is distributed over at least one of frequency and time. ### Claim 57 (depends on 48) The method of claim 48, wherein detecting the first pilot transmission and the second pilot transmission comprises: detecting whether at least a portion of the first pilot transmission and the second pilot transmission is shared between the first device and the second device.