# US 2014/0153425 A1 · Neighbour Cell Quality Measurement in a Telecommunications System > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0153425 A1 - Document ID: US20140153425A1 - Status: Published application - Kind: A1 - Application number: 14/102,627 - Filed: 2013-12-11 - Published: 2014-06-05 - Earliest claimed: 2010-09-10 - Assignees: Telefonaktiebolaget LM Ericsson (publ) - Applicants: Telefonaktiebolaget Lm Ericsson (Publ) - Inventors: Muhammad Kazmi; George Jöngren - Web page: https://patentgrep.com/patent/US20140153425A1 ## CPC - H04L 5/006: {Quality of the received signal, e.g. BER, SNR, water filling} - H04J 11/005: {of intercell interference} - H04J 11/0093: {Neighbour cell search} - H04L 5/0039: {Frequency-contiguous, i.e. with no allocation of frequencies for one user or terminal between the frequencies allocated to another} - H04W 24/08: Testing, {supervising or monitoring} using real traffic - H04W 24/10: Scheduling measurement reports {; Arrangements for measurement reports} - H04W 36/0085: {Hand-off measurements} - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) - H04J: MULTIPLEX COMMUNICATION (transmission in general H04B; peculiar to transmission of digital information H04L5/00; systems for the simultaneous or sequential transmission of more than one television signal H04N7/08; in exchanges H04Q11/00; stereophonic systems H04S) - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) ## Abstract The present invention relates to methods and arrangements for neighbour cell quality measurements using silent resource element (RE) grids, and as well to a silent RE grid. ## Claims ### Claim at position 1 1-34. (canceled) ### Claim 35 A first method, executed in a first network node of a wireless communication system, for measuring a quality of a neighbor cell for mobility purposes, the method comprising: deriving a cell-specific silent grid, the cell-specific silent grid comprising resource elements having no data allocation; measuring signal interference over said grid during a measurement period; and estimating the quality of the neighbor cell based on the measured signal interference. ### Claim 36 (depends on 1) A first method according to claim 1, further comprising a step of reporting said estimated quality of the neighbor cell to a second network node. ### Claim 37 (depends on 1) A first method according to claim 1, further comprising calculating the quality of the neighbor cell as an inter-cell interference that is measured or estimated during the cell-specific silent grid. ### Claim 38 (depends on 37) A first method according to claim 37, wherein the inter-cell interference comprises noise and a received power from a data channel or a control channel, or a combination thereof. ### Claim 39 (depends on 37) A first method according to claim 37, further comprising calculating the quality of the neighbor cell using signal strength and interference. ### Claim 40 (depends on 37) A first method according to claim 37, further comprising calculating the quality of the neighbor cell as a Reference Symbol Received Quality (RSRQ) using the following equation: RSRQ=RSRP/(Iinter-cell+N0), where RSRP=Reference Symbol Received Power, Iinter-cell=inter-cell interference measured during the silent resource element grid used in cell i, and N0=noise. ### Claim 41 (depends on 37) A first method according to claim 37, further comprising defining a position in the cell-specific silent grid of the resource elements having no data allocation, as a function of a cell ID of the cell corresponding to the cell-specific silent grid. ### Claim 42 (depends on 37) A first method according to claim 37, further comprising deriving the cell-specific silent grid for the first network node, from a cell ID of the neighbor cell; and making the cell-specific silent grid known to the first network node. ### Claim 43 (depends on 37) A first method according to claim 37, further comprising signaling or sending an index of the cell-specific silent grid, to the first network node, via at least one control channel. ### Claim 44 (depends on 43) A first method according to claim 43, wherein the at least one control channel is a broadcast channel mapped on, or sent via, a physical downlink shared channel (PDSCH). ### Claim 45 A first arrangement in a first network node, configured to: derive a cell-specific silent grid to measure a quality of a neighbor cell, the cell-specific silent grid comprising data resource elements with no data allocation; measure an inter-cell interference during said silent grid over a measurement period; and estimate the quality of the neighbor cell based on the measured signal interference. ### Claim 46 (depends on 45) A first arrangement according to claim 45, further configured to report said estimated quality of the neighbor cell to a second network node. ### Claim 47 (depends on 45) A first arrangement according to claim 45, wherein the first arrangement is configured to estimate the quality of the neighbor cell based on measuring the inter-cell interference during the cell-specific silent grid. ### Claim 48 (depends on 45) A first arrangement according to claim 45, wherein the inter-cell interference comprises noise and a received power from a data channel or control channel, or a combination thereof. ### Claim 49 (depends on 45) A first arrangement according to claim 45, wherein the first arrangement is configured to estimate the quality of the neighbor cell based on measuring signal strength and interference, the interference including the inter-cell interference and noise. ### Claim 50 (depends on 45) A first arrangement according to claim 45, wherein the first arrangement is configured to estimate the quality of the neighbor cell based on calculating a Reference Symbol Received Quality (RSRQ) using the following equation: RSRQ=RSRP/(Iinter-cell+N0), where RSRP=Reference Symbol Received Power, Iinter-cell=inter-cell interference measured during the cell-specific silent grid used in the neighbor cell and N0=noise. ### Claim 51 (depends on 45) A first arrangement according to claim 45, further configured to define the position in the cell-specific silent grid as a function of a cell ID of the neighbor cell. ### Claim 52 (depends on 45) A first arrangement according to claim 45, wherein: the cell-specific silent grid is derived from a cell ID of the neighbor cell; and the cell-specific silent grid is made known to the first network node. ### Claim 53 (depends on 45) A first arrangement according to claim 45, further configured to transmit an index of the cell-specific silent grid to the first network node, via one or more control channels. ### Claim 54 (depends on 53) A first arrangement according to claim 53, wherein the arrangement is configured to transmit the index of the cell-specific silent grid via a secondary or a dedicated broadcast channel (D-BCH), or a physical downlink shared channel (PDSCH). ### Claim 55 A second method executed in a second network node of a wireless communication system, for configuring a cell-specific silent grid for use in neighbor cell quality measurements by a first network node of the wireless communication system, wherein the method comprises at least one of the following steps: configuring at least one of the resource elements in said cell-specific silent grid to have no data allocation, thereby achieving a cell-specific silent grid; configuring at least some of the resource elements in said cell-specific silent grid which can be used for data transmission to have no data allocation; randomizing the cell-specific silent grid in consecutive, in frequency and time, resource blocks; or changing the cell-specific silent grid randomly, in frequency and time. ### Claim 56 (depends on 55) A second method according to claim 55, said cell-specific silent grid comprising resource elements organized in resource blocks, time slots, sub-frames and frames, and the method further including grouping, suitably for each sub frame, the resource blocks into resource windows, wherein each resource window suitably comprises a group of resource blocks contiguous in frequency. ### Claim 57 (depends on 55) A second method according to claim 55, further comprising, suitably for each resource window, enumerating all resource elements that are not used for control or reference symbol signaling. ### Claim 58 (depends on 57) A second method according to claim 57, further comprising selecting, suitably in each resource window, a specified number of silent resource elements from the set of the enumerated resource elements using a pseudo-random number generator that generates numbers uniformly in the range of the enumerated data resource elements. ### Claim 59 (depends on 55) A second method according to claim 55, further comprising signaling an index of the cell-specific silent grid used in a neighbor cell to the first network node, via one or more control channels. ### Claim 60 (depends on 59) A second method according to claim 59, wherein the one or more control channels is a broadcast channel mapped on, or sent via, a physical downlink shared channel (PDSCH). ### Claim 61 A second arrangement in a second network node of a wireless communication system, said arrangement comprising at least one processor configured to: configure a cell-specific silent grid, for use in neighbor cell quality measurements by a first network node of a wireless communication system; configure at least one of the resource elements in said cell-specific silent grid to have no data allocation, thereby achieving a cell-specific silent grid; configure at least some of the resource elements in said cell-specific silent grid which can be used for data transmission, to have no data allocation, thereby achieving a cell-specific silent grid, randomize said cell-specific silent grid in consecutive, in frequency and time, resource blocks, change said cell-specific silent grid randomly, in frequency and time. ### Claim 62 (depends on 61) A second arrangement according to claim 61, said cell-specific silent grid comprising resource elements organized in resource blocks, time slots, sub-frames and frames, and wherein the at least one processor is further configured to group, suitably for each sub frame, the resource blocks into resource windows, wherein each resource window suitably comprises a group of resource blocks contiguous in frequency. ### Claim 63 (depends on 61) A second arrangement according to claim 61, wherein the at least one processor is further configured to, for each resource window, enumerate all resource elements that are not used for control or reference symbol signaling. ### Claim 64 (depends on 63) A second arrangement according to claim 63, wherein the at least one processor is further configured to select, in each resource window, a specified number of silent resource elements from the set of the enumerated resource elements by using a pseudo-random number generator that generates numbers uniformly in the range of the enumerated resource elements. ### Claim 65 (depends on 61) A second arrangement according to claim 61, wherein the at least one processor is further configured to signal an index of the cell-specific silent grid used in the neighbor cell to the first network node via at least one control channel. ### Claim 66 (depends on 65) A second arrangement according to claim 65, wherein the index of the cell-specific silent grid is sent via a secondary or a dedicated broadcast channel (D-BCH) on, or a physical downlink shared channel (PDSCH).