Modulation index shift signaling

Patent metadata

Field	Value
Publication number	US-9847895-B2
Application number	US-201514430573-A
Country	US
Kind code	B2
Filing date	Feb 4, 2015
Priority date	Feb 4, 2015
Publication date	Dec 19, 2017
Grant date	Dec 19, 2017

Abstract

A transmitting device ( 20 ) overlays control information onto information bit stream intended for a receiving device ( 40 ) by varying or shifting the modulation index in continuous phase modulation (CPM) waveform. The receiving device ( 40 ) detects the modulation index used at the transmitting device ( 20 ) to modulate the data burst. The receiving device ( 40 ) then determines the control information based on the detected modulation index.

First claim

What is claimed is:

1. A method of sending control information from a transmitting device to a receiving device, the method comprising:
generating a modulated signal that signals the control information to the receiving device by mapping the control information to a selected modulation index set and modulating an information bit stream for the receiving device with a continuous phase modulator using the selected modulation index set; and
transmitting the modulated signal to the receiving device.

2. The method of claim 1 wherein the modulation index set comprises a single index value applied to selected information bits in said information bit stream.

3. The method of claim 1 wherein the modulation index set comprises a sequence of index values applied to respective ones of selected information bits in said information bit stream.

4. The method of claim 1 wherein modulating an information bit stream for the receiving device comprises modulating an known bit sequence in the information bit stream that is known to the receiving device using the selected modulation index set.

5. The method of claim 4 wherein modulating the known bit sequence comprises modulating a predefined synchronization sequence in the information bit stream using the selected modulation index set.

6. The method of claim 1 wherein each modulation index in the modulation index set is set to one of a first value or a second value.

7. The method of claim 6 wherein modulating an information bit stream for the receiving device comprises:
inverting the sign of each selected information bit in the information bit stream when the value of a corresponding modulation index in the modulation index set is the second value to generate a modified information bit stream; and
modulating the modified information bit stream in the continuous phase modulator using a fixed modulation index corresponding to the first value.

8. The method of claim 6 wherein modulating an information bit stream with a continuous phase modulator using the selected modulation index set comprises:
modulating the information bit stream in the continuous phase modulator using a fixed modulation index corresponding to the first value to generate an initial signal;
conjugating selected ones of the modulation symbols in the initial signal when a corresponding modulation index in the modulation index set is the second value to generate the modulated signal.

9. The method of claim 1 wherein the information bit stream includes user data bits and wherein the control information comprises data rate information for the user data bits in the information bit stream.

10. A transmitting device configured to send control information to a receiving device comprising:
a processing circuit configured to generate a modulated signal that signals control information to a receiving device by mapping the control information for the receiving device to a selected modulation index set and modulating an information bit stream with a continuous phase modulator using the selected modulation index set; and
a transmitter configured to transmit the modulated information bit steam to a receiving device.

11. The transmitting device of claim 10 wherein the modulation index set comprises a single index value applied to selected information bits in said information bit stream.

12. The transmitting device of claim 10 wherein the modulation index set comprises a sequence of index values applied to respective ones of selected information bits in said information bit stream.

13. The transmitting device of claim 10 wherein the processing circuit is configured to modulate a known bit sequence in the information bit stream that is known to the receiving device using the selected modulation index set.

14. The transmitting device of claim 13 wherein the wherein the continuous phase modulator is configured to modulate a predefined synchronization sequence in the information bit stream using the selected modulation index set.

15. The transmitting device of claim 10 wherein each modulation index in the modulation index set used by the processing circuit is set to one of a first value or a second value.

16. The transmitting device of claim 15 wherein the processing circuit is configured to modulate the information bit stream by:
inverting the sign of each selected information bit in the information bit stream when the value of a corresponding modulation index in the modulation index set is the second value to generate a modified information bit stream; and
modulating the modified information bit stream using a fixed modulation index corresponding to the first value.

17. The transmitting device of claim 15 wherein the processing circuit is configured to modulate the information bit stream by:
modulating the information bit stream with the continuous phase modulator using a fixed modulation index corresponding to the first value to generate an initial signal; and
conjugating selected ones of the modulation symbols in the initial signal when a corresponding modulation index in the modulation index set is the second value to generate the modulated signal.

18. The transmitting device of claim 10 wherein the information bit stream includes user data bits and wherein the control information comprises data rate information for the user data bits in the information bit stream.

19. A method of receiving control information from a transmitting device, the method comprising:
receiving, from the transmitting device, a modulated signal generated by modulating an information bit stream in a continuous phase modulator using a predefined modulation index set;
processing the modulated signal to detect the modulation index set used by the transmitting device to generate the modulated signal; and
determining the control information by mapping the modulation index set to a corresponding one of a predefined set of control information.

20. The method of claim 19 wherein the modulation index set comprises a single index value applied to selected information bits in said information bit stream.

21. The method of claim 19 wherein the modulation index set comprises a sequence of index values applied to respective ones of selected information bits in said information bit stream.

22. The method of claim 19 wherein processing the modulated signal to detect the modulation index set comprises processing a portion of the modulated signal containing a known bit sequence to detect the modulation index set.

23. The method of claim 22 wherein processing a portion of the modulated signal containing a known bit sequence to detect the modulation index set comprises processing a portion of the modulated signal containing a known bit sequence to jointly detect the modulation index set and time synchronization.

24. The method of claim 19 wherein processing the modulated signal to detect the modulation index set comprises correlating the modulated signal with one or more known modulation symbol sequences.

25. The method of claim 24 wherein correlating the modulated signal with one or more known modulation sequences comprises correlating a first portion of the modulated signal with a first predetermined index sequence and correlating a second portion of the modulated signal with a second predetermined index sequence.

26. The method of claim 19 wherein the information bit stream includes user data bits and further comprising:
demod

Assignees

• Ericsson Telefon Ab L M
• ERICSSON TELEFON AB L M (publ)

Inventors

• Lopez Miguel
• Hagerman Bo
• Wang Yi-Pin Eric

Classifications

• H04L5/0053 Primary

  Allocation of signalling, i.e. of overhead other than pilot signals · CPC title

• H04L27/2003 Primary

  for continuous phase modulation (frequency shift keying H04L27/10) · CPC title

• H04L27/22

  Demodulator circuits; Receiver circuits · CPC title

• H04L27/201

  in which the allowed phase changes vary with time, e.g. multi-h modulation · CPC title

• H04W4/008

  Electricity · mapped topic