# US 2018/0324731 A1 · Physical channel configuration method, base station and user equipment

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- Number: US 2018/0324731 A1
- Document ID: US20180324731A1
- Status: Published application
- Kind: A1
- Application number: 15/773,669
- Filed: 2016-11-04
- Published: 2018-11-08
- Earliest claimed: 2015-11-05
- Assignees: Sharp Kabushiki Kaisha
- Applicants: Sharp Kabushiki Kaisha
- Inventors: RENMAO LIU; MENG ZHANG
- Web page: https://patentgrep.com/patent/US20180324731A1

## CPC

- H04W 56/0015: {one node acting as a reference for the others}
- H04L 5/0007: {the frequencies being orthogonal, e.g. OFDM(A) or DMT}
- H04L 5/0048: {Allocation of pilot signals, i.e. of signals known to the receiver (allocation of control signalling H04L5/0053; use of control signalling H04L5/0091)}
- H04L 27/26136: {Pilot sequence conveying additional information}
- H04L 27/2656: {Frame synchronisation, e.g. packet synchronisation, time division duplex [TDD] switching point detection or subframe synchronisation}
- H04L 27/2657: {Carrier synchronisation}
- H04L 27/2666: {Acquisition of further OFDM parameters, e.g. bandwidth, subcarrier spacing, or guard interval length}
- H04L 27/2692: {with preamble design, i.e. with negotiation of the synchronisation sequence with transmitter or sequence linked to the algorithm used at the receiver}
- H04W 72/23: in the downlink direction of a wireless link, i.e. towards a terminal
- H04J 11/0069: {Cell search, i.e. determining cell identity [cell-ID] (design of multiplexing codes H04J13/00; processing access restriction or access information H04W48/16; discovery of network devices for network data management H04W8/005; sounding signals for channel estimation H04L25/0226; structure of reference signals in multicarrier modulation systems H04L27/2613; frame, time or carrier synchronisation in multicarrier modulation systems H04L27/2655)}
- 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)
- 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)

## Abstract

The present invention provides a method for transmitting downlink signals, which is suitable for narrow-band systems such as NB-IOT, eMTC and MMTC, and a base station and a user equipment for performing the method. The method comprises: detecting synchronization signals; determining a starting OFDM symbol for downlink reception according to the detected synchronization signals; and receiving downlink signals according to the determined starting OFDM symbol.

## Claims

### Claim 1

A method performed in a user equipment, comprising: detecting synchronization signals; determining a starting OFDM symbol for downlink reception according to the detected synchronization signals; and receiving downlink signals according to the determined starting OFDM symbol.

### Claim 2 (depends on 1)

The method according to claim 1, wherein the starting OFDM symbol is implicitly or explicitly indicated with synchronization signals.

### Claim 3 (depends on 1)

The method according to claim 1, wherein the synchronization signals refer to primary synchronization signals and/or secondary synchronization signals.

### Claim 4 (depends on 3)

The method according to claim 3, wherein the determination step further comprises: determining the starting OFDM symbol according to a sequence number of detected primary synchronization signals; or
determining the starting OFDM symbol according to a sequence number of detected secondary synchronization signals; or
determining the starting OFDM symbol according to a group number of the detected secondary synchronization signals.

### Claim at position 5

-7. (canceled)

### Claim 8 (depends on 3)

The method according to claim 3, wherein the determination step further comprises: determining the starting OFDM symbol according to relative positions of the detected primary synchronization signals and the detected secondary synchronization signals in a time domain and/or a frequency domain; or
determining the starting OFDM symbol according to different combination modes of multiple sequences in the detected secondary synchronization signals.

### Claim 9

(canceled)

### Claim 10

A method performed in a base station, the method comprising: transmitting synchronization signals; determining a starting OFDM symbol for downlink transmission according to used synchronization signals; and transmitting downlink signals according to the determined starting OFDM symbol.

### Claim 11 (depends on 10)

The method according to claim 10, wherein the starting OFDM symbol is implicitly or explicitly indicated with synchronization signals.

### Claim 12 (depends on 10)

The method according to claim 10, wherein the synchronization signals refer to primary synchronization signals and/or secondary synchronization signals.

### Claim 13 (depends on 12)

The method according to claim 12, wherein the determination step further comprises: determining the starting OFDM symbol according to a sequence number of used primary synchronization signals; or
determining the starting OFDM symbol according to a sequence number of used secondary synchronization signals; or
determining the starting OFDM symbol according to a group number of the used secondary synchronization signals.

### Claim at position 12

-16. (canceled)

### Claim 17 (depends on 12)

The method according to claim 12, wherein the determination step further comprises: determining the starting OFDM symbol according to relative positions of the used primary synchronization signals and the used secondary synchronization signals in a time domain and/or a frequency domain; or
determining the starting OFDM symbol according to different combination modes of multiple sequences in the used secondary synchronization signals.

### Claim 18

(canceled)

### Claim 19

A user equipment, comprising: detecting circuitry, configured to detect synchronization signals; processing circuitry, configured to determine a starting OFDM symbol for downlink reception according to the detected synchronization signals; and receiving circuitry, configured to receive downlink signals according to the determined starting OFDM symbol.

### Claim 20 (depends on 19)

The user equipment according to claim 19, wherein the starting OFDM symbol is implicitly or explicitly indicated with the synchronization signals.

### Claim 21 (depends on 19)

The user equipment according to claim 19, wherein the synchronization signals refer to primary synchronization signals and/or secondary synchronization signals.

### Claim 22 (depends on 21)

The user equipment according to claim 21, wherein the processing circuitry is further configured to: determine the starting OFDM symbol according to a sequence number of detected primary synchronization signals; or
determine the starting OFDM symbol according to a sequence number of detected secondary synchronization signals; or
determine the starting OFDM symbol according to a group number of the detected secondary synchronization signals.

### Claim at position 19

-25. (canceled)

### Claim 26 (depends on 21)

The user equipment according to claim 21, wherein the processing circuitry is further configured to: determine the starting OFDM symbol according to relative positions of the detected primary synchronization signals and the detected secondary synchronization signals in a time domain and/or a frequency domain; or
determine the starting OFDM symbol according to different combination modes of multiple sequences in the detected secondary synchronization signals.

### Claim 27

(canceled)

### Claim 28

A base station, comprising: processing circuitry, configured to determine a starting OFDM symbol for downlink transmission according to used synchronization signals; and transmitting circuitry, configured to transmit the synchronization signals, and transmit downlink signals according to the determined starting OFDM symbol.

### Claim 29 (depends on 28)

The base station according to claim 28, wherein the starting OFDM symbol is implicitly or explicitly indicated with the synchronization signals.

### Claim 30 (depends on 28)

The base station according to claim 28, wherein the synchronization signals refer to primary synchronization signals and/or secondary synchronization signals.

### Claim 31 (depends on 30)

The base station according to claim 30, wherein the processing circuitry is further configured to: determine the starting OFDM symbol according to a sequence number of used primary synchronization signals; or
determine the starting OFDM symbol according to a sequence number of used secondary synchronization signals; or
determine the starting OFDM symbol according to a group number of the used secondary synchronization signals.

### Claim at position 26

-34. (canceled)

### Claim 35 (depends on 30)

The base station according to claim 30, wherein the processing circuitry is further configured to: determine the starting OFDM symbol according to relative positions of the used primary synchronization signals and the used secondary synchronization signals in a time domain and/or a frequency domain; or
determine the starting OFDM symbol according to different combination modes of multiple sequences in the used secondary synchronization signals.

### Claim 36

(canceled)