Communication transmission with super-gaussian filtering in receiver

• US 10,158,504 B2
• Filed: 01/29/2018
• Issued: 12/18/2018
• Est. Priority Date: 02/01/2017
• Status: Active Grant

• Current Assignee: Roshmere, Inc.
• Original Assignee: Roshmere, Inc.
• Inventors: Alic, Nikola, Giraldo, Eduardo Temprana
• Primary Examiner(s): Joseph, Jaison
• Application Number:
  US15/882,862
• Publication Number:
  US 20180219702A1
• Time in Patent Office: 323 Days
• CPC Class Codes: H04L 25/03006 Arrangements for removing intersymbol interference
• CPC Class Codes: H04L 25/03834 using pulse shaping

Abstract

In a transmission system, a transmission signal is generated from transmission data. The transmission signal has a series of shaped pulses, such as raised-cosine or root-raised-cosine shaped pulses. A reception signal, based on the transmission signal having passed through a transmission channel, is sampled to generate sampled digital data. The sampled digital data is filtered through a super-Gaussian filter to regenerate the transmission data.

Claims

1. A method comprising:

receiving, by a transmitter, transmission data;

generating, by the transmitter, a transmission signal from the transmission data, the transmission signal having a series of shaped pulses;

transmitting, by the transmitter, the transmission signal;

receiving, by a receiver, a reception signal based on the transmission signal having passed through a transmission channel;

sampling, by the receiver, the reception signal to generate sampled digital data; and

filtering, by the receiver, the sampled digital data through a super-Gaussian filter to regenerate the transmission data;

wherein the transmitter generates the shaped pulses using a pulse shaping filter selected from the group consisting of raised-cosine filter and root-raised-cosine filter families.

2. The method of claim 1, wherein:

the super-Gaussian filter in the receiver has excess bandwidth compared to the pulse shaping filter in the transmitter.

3. The method of claim 2, wherein:

the excess bandwidth in the super-Gaussian filter in the receiver is at least as large as a roll-off-factor of the pulse shaping filter used to generate the transmitted signal.

4. The method of claim 1, wherein:

the super-Gaussian filter operates with 4-16 sampling points to generate the sampled digital data.

5. The method of claim 1, wherein:

the super-Gaussian filter operates with a maximum of 4 sampling points to generate the sampled digital data.

6. The method of claim 1, wherein:

the super-Gaussian filter operates according to a super-Gaussian function having an exponent of 4 or more.

7. The method of claim 1, wherein:

the transmission signal is an optical signal; and

the transmission channel is a fiber-optic channel.

8. The method of claim 1, wherein:

the transmission signal is an RF signal; and

the transmission channel is air.

9. The method of claim 1, wherein:

the transmitter further generates the shaped pulses also using a second pulse shaping filter that shapes the pulses operating according to a function G(ω

); and

the filtering at the receiver further comprises filtering the sampled digital data using a filter operating according to a function 1/G(ω

).

10. A transmission system comprising:

a transmitter having a pulse-shaping filter with which the transmitter generates a transmission signal with a series of shaped pulses for transmission, the series of shaped pulses being generated from digital transmission data; and

a receiver having a super-Gaussian filter with which the receiver regenerates the digital transmission data from sampled digital data of a reception signal based on the transmission signal having passed through a transmission channel;

wherein the pulse shaping filter is selected from the group consisting of a raised-cosine filter, or a root-raised-cosine filter.

11. The transmission system of claim 10, wherein:

the super-Gaussian filter in the receiver has excess bandwidth compared to the pulse shaping filter in the transmitter.

12. The transmission system of claim 11, wherein:

the excess bandwidth in the super-Gaussian filter in the receiver is at least as large as a roll-off-factor of the pulse shaping filter in the transmitter.

13. The transmission system of claim 10, wherein:

the super-Gaussian filter operates with 4-16 sampling points to generate the sampled digital data.

14. The transmission system of claim 10, wherein:

the super-Gaussian filter operates with a maximum of 4 sampling points to generate the sampled digital data.

15. The transmission system of claim 10, wherein:

the super-Gaussian filter operates according to a super-Gaussian function having an exponent of 4 or more.

16. The transmission system of claim 10, wherein:

the transmission signal is an optical signal; and

the transmission channel is an optical channel.

17. The transmission system of claim 10, wherein:

the transmission signal is an RF signal; and

the transmission channel is air.

18. The transmission system of claim 10, wherein:

the transmitter further comprises a second pulse shaping filter, wherein the second pulse shaping filter shapes the pulses operating according to a function G(ω

); and

the receiver further comprises a filter operating according to a function 1/G(ω

) which compensates for a departure of the transmitter and receiver overall transfer characteristic from a Nyquist condition for ISI-free communication.

19. A method comprising:

receiving, by a receiver, a reception signal based on a transmission signal having passed through a transmission channel, the transmission signal having been formed with a series of shaped pulses, and the transmission signal having been formed from digital transmission data;

sampling, by the receiver, the reception signal to generate sampled digital data;

filtering, by the receiver, the sampled digital data through a super-Gaussian filter to regenerate the digital transmission data;

wherein the shaped pulses are shaped using a pulse shaping filter selected from the group consisting of a raised-cosine filter, or a root-raised-cosine filter.

20. The method of claim 19, wherein:

the super-Gaussian filter in the receiver has excess bandwidth compared to the pulse shaping filter in the transmitter.

21. The method of claim 20, wherein:

the excess bandwidth in the super-Gaussian filter in the receiver is at least as large as a roll-off-factor of the pulse shaping filter in the transmitter.

22. The method of claim 19, wherein:

the super-Gaussian filter operates with 4-16 sampling points to generate the sampled digital data.

23. The method of claim 19, wherein:

the super-Gaussian filter operates with a maximum of 4 sampling points to generate the sampled digital data.

24. The method of claim 19, wherein:

the super-Gaussian filter operates according to a super-Gaussian function having an exponent of 4 or more.

25. The method of claim 19, wherein:

the reception signal is an optical signal; and

the transmission channel is an optical channel.

26. The method of claim 19, wherein:

the transmission signal is an RF signal; and

the transmission channel is air.

27. The method of claim 19, wherein:

the shaped pulses are further shaped using a second pulse shaping filter, wherein the second pulse shaping filter shapes the pulses using a function G(ω

); and

the filtering at the receiver further comprises filtering the sampled digital data using a filter with the function 1/G(ω

), thus compensating for a departure of the transmitter and receiver overall transfer characteristic from a Nyquist condition for ISI-free communication.