Multi-modulation receiver, transmitters and methods for handling multi-modulation in wireless communication systems

• US 10,187,233 B2
• Filed: 03/31/2016
• Issued: 01/22/2019
• Est. Priority Date: 03/31/2016
• Status: Active Grant

• Current Assignee: Telefonaktiebolaget LM Ericsson
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: Wilhelmsson, Leif, Lopez, Miguel
• Primary Examiner(s): Guarino, Rahel
• Application Number:
  US15/031,527
• Publication Number:
  US 20180091337A1
• Time in Patent Office: 1,027 Days
• CPC Class Codes: H04L 27/0008 arrangements for allowing a transmitter or receiver to use more than one type of modulation negotiating modulation type for two-way transmission paths H04L5/1453
• CPC Class Codes: H04L 27/14 Demodulator circuits; Receiver circuits
• CPC Class Codes: H04L 27/2601 Multicarrier modulation systems
• CPC Class Codes: H04L 27/26524 Fast Fourier transform [FFT] or discrete Fourier transform [DFT] demodulators in combination with other circuits for demodulation
• CPC Class Codes: H04W 4/70 Services for machine-to-machine communication [M2M] or machine type communication [MTC]
• CPC Class Codes: H04W 84/12 WLAN [Wireless Local Area Networks]

Abstract

A multi-modulation receiver configured to receive a multicarrier signal comprising data transmitted from multiple transmitters. At least one of the transmitters is a transmitter using a modulation scheme other than Orthogonal Frequency-Division Multiplexing. Data transmitted from different transmitters are mapped to different subcarriers in the frequency domain. The multi-modulation receiver has a radio unit configured to receive the multicarrier signal. A cyclic prefix unit is configured to remove a Cyclic Prefix from the received multicarrier signal. A Fast Fourier Transform unit is configured to separate data received from the individual transmitters into mutually orthogonal subcarriers by transforming the multicarrier signal in the time domain to multiple orthogonal subcarrier signals in the frequency domain. A demapping unit is configured to, for each of the multiple transmitters, demap the corresponding subcarrier signals in accordance with the modulation scheme of the respective transmitter.

Claims

1. A multi-modulation receiver configured to receive a multicarrier signal comprising data transmitted from multiple transmitters, at least one of the transmitters is a transmitter using a modulation scheme other than Orthogonal Frequency-Division Multiplexing, OFDM, and data transmitted from different transmitters are mapped to different subcarriers in a frequency domain, the multi-modulation receiver comprising:

a radio unit configured to receive the multicarrier signal;

a cyclic prefix unit configured to remove a Cyclic Prefix, CP, from the received multicarrier signal;

a Fast Fourier Transform, FFT, unit configured to separate data received from the individual transmitters into mutually orthogonal subcarriers by transforming the multicarrier signal in a time domain to multiple orthogonal subcarrier signals in the frequency domain; and

a demapping unit configured to, for each of the multiple transmitters, demap the corresponding subcarrier signals in accordance with the modulation scheme of the respective transmitter.

2. The multi-modulation receiver according to claim 1, wherein at least one of the multiple transmitters is an OFDM transmitter.

3. The multi-modulation receiver according to claim 2, wherein the transmitter using a modulation scheme other than OFDM has a lower data rate than the OFDM transmitter.

4. The multi-modulation receiver according to claim 2, wherein the OFDM transmitter operates in accordance with one of IEEE 802.11 and 802.11ax.

5. The multi-modulation receiver according to claim 1, wherein the demapping unit is configured to demap the data such that data transmitted from different transmitters are mapped to in the frequency domain mutually orthogonal subcarriers.

6. The multi-modulation receiver according to claim 1, wherein the transmitter using a modulation scheme other than OFDM is a single carrier transmitter.

7. The multi-modulation receiver according to claim 1, wherein the transmitter using a modulation scheme other than OFDM is a Frequency-Shift Keying, FSK, transmitter.

8. The multi-modulation receiver according to claim 1, wherein the demapping unit is configured to demap the data such that the demapping is performed based on output amplitudes after the transformation to the frequency domain.

9. A network node in a wireless communication network comprising a multi-modulation receiver, the multi-modulation receiver being configured to receive a multicarrier signal comprising data transmitted from multiple transmitters, at least one of the transmitters is a transmitter using a modulation scheme other than Orthogonal Frequency-Division Multiplexing, OFDM, and data transmitted from different transmitters are mapped to different subcarriers in a frequency domain, the multi-modulation receiver comprising:

a radio unit configured to receive the multicarrier signal;

a cyclic prefix unit configured to remove a Cyclic Prefix, CP, from the received multicarrier signal;

a Fast Fourier Transform, FFT, unit configured to separate data received from the individual transmitters into mutually orthogonal subcarriers by transforming the multicarrier signal in a time domain to multiple orthogonal subcarrier signals in the frequency domain; and

a demapping unit configured to, for each of the multiple transmitters, demap the corresponding subcarrier signals in accordance with the modulation scheme of the respective transmitter.

10. A non-OFDM transmitter for transmitting data to a multi-modulation receiver, the mufti-modulation receiver being configured to receive an OFDM signal, the non-OFDM transmitter comprising:

a mapping unit configured to, in a first transmission mode, map data targeting the multi-modulation receiver on a subcarrier signal, using a repetition code matching an OFDM symbol duration of the multi-modulation receiver, the repetition code corresponding to a repetition of a symbol in the non-OFDM transmitter; and

a radio unit configured to transmit the subcarrier signal to the multi-modulation receiver.

11. The non-OFDM transmitter according to claim 10, wherein the mapping unit is configured to, in a second transmission mode, use another repetition code.

12. The non-OFDM transmitter according to claim 11, wherein the mapping unit is configured to switch between the first and second transmission modes.

13. The non-OFDM transmitter according to claim 11, wherein the first and second transmission modes use different modulation schemes.

14. The non-OFDM transmitter according to claim 10, wherein the repetition code is such that an accumulated duration of repetitions of one symbol in the non-OFDM transmitter equals a duration of an input to a Fast Fourier Transform, FFT, plus a duration of a cyclic prefix, CP, of one OFDM symbol.

15. The non-OFDM transmitter according to claim 10, wherein the non-OFDM transmitted is included as a part of a wireless device.

16. A method for receiving a multicarrier signal comprising data transmitted from multiple transmitters, at least one of the transmitters is an Orthogonal Frequency-Division Multiplexing, OFDM, transmitter, at least one of the transmitters is a transmitter using a modulation scheme other than OFDM, and data transmitted from different transmitters are mapped different subcarriers in a frequency domain, the method comprising:

receiving the multicarrier signal;

removing a Cyclic Prefix, CP, from the multicarrier signal;

separating data received from the individual transmitters by transforming the multicarrier signal in a time domain to multiple orthogonal subcarrier signals in the frequency domain; and

demapping, for each of the multiple transmitters, the corresponding subcarrier signals in accordance with the modulation scheme of the transmitter.

17. The method according to claim 16, wherein the different subcarriers are mutually orthogonal in the frequency domain.

18. A non-transitory computer storage media storing computer program code which, when executed by a processor on a multi-modulation receiver, causes the multi-modulation receiver to perform a method for receiving a multicarrier signal comprising data transmitted from multiple transmitters, at least one of the transmitters is an Orthogonal Frequency-Division Multiplexing, OFDM, transmitter, at least one of the transmitters is a transmitter using a modulation scheme other than OFDM, and data transmitted from different transmitters are mapped different subcarriers in a frequency domain, the method comprising:

receiving the multicarrier signal;

removing a Cyclic Prefix, CP, from the multicarrier signal;

separating data received from the individual transmitters by transforming the multicarrier signal in a time domain to multiple orthogonal subcarrier signals in the frequency domain; and

demapping, for each of the multiple transmitters, the corresponding subcarrier signals in accordance with the modulation scheme of the transmitter.

19. A method for transmitting data to a multi-modulation receiver, the multi-modulation receiver being configured to receive an OFDM signal, the method comprising:

in a first transmission mode, mapping data targeting the multi-modulation receiver on a signal, using a repetition code matching an OFDM symbol duration of the multi-modulation receiver, the repetition code corresponding to a repetition of a symbol in the non-OFDM transmitter; and

transmitting a subcarrier signal to the multi-modulation receiver.

20. The method according to claim 19, the method further comprising:

switching between the first and a second transmission mode, wherein the second transmission mode uses another repetition code.

21. A non-transitory computer storage media storing computer program code which, when executed by a processor on a wireless device, the wireless comprising a non-OFDM transmitter for transmitting data to a multi-modulation receiver, the multi-modulation receiver being configured to receive an OFDM signal,

causes the wireless device to perform a method, the method comprising:

in a first transmission mode, mapping data targeting the multi-modulation receiver on a signal, using a repetition code matching an OFDM symbol duration of the multi-modulation receiver, the repetition code corresponding to a repetition of a symbol in the non-OFDM transmitter; and

transmitting the subcarrier signal to the multi-modulation receiver.