COMMUNICATION TRANSMISSION WITH SUPER-GAUSSIAN FILTERING IN RECEIVER

• US 20180219702A1
• Filed: 01/29/2018
• Published: 08/02/2018
• Est. Priority Date: 02/01/2017
• Status: Active Grant

• Current Assignee: Roshmere, Inc.
• Original Assignee: Roshmere, Inc.
• Inventors: Alic, Nikola, Giraldo, Eduardo Temprana
• Granted Patent: US 10,158,504 B2
• Time in Patent Office: 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.

2. The method of claim 1, 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.

3. The method of claim 2, wherein:

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

4. The method of claim 3, 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.

5. The method of claim 1, wherein:

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

6. The method of claim 1, wherein:

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

7. The method of claim 1, wherein:

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

8. The method of claim 1, wherein:

the transmission signal is an optical signal; and

the transmission channel is a fiber-optic channel.

9. The method of claim 1, wherein:

the transmission signal is an RF signal; and

the transmission channel is air.

10. The method of claim 1, wherein:

the transmitter generates the shaped pulses using first and second pulse shaping filters, wherein the first pulse shaping filter is selected from the group consisting of a raised-cosine filter and a root-raised-cosine filter, and the second pulse shaping filter 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

).

11. 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.

12. The transmission system of claim 11, wherein:

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

13. The transmission system of claim 12, wherein:

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

14. The transmission system of claim 13, 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.

15. The transmission system of claim 11, wherein:

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

16. The transmission system of claim 11, wherein:

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

17. The transmission system of claim 11, wherein:

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

18. The transmission system of claim 11, wherein:

the transmission signal is an optical signal; and

the transmission channel is an optical channel.

19. The method of claim 11, wherein:

the transmission signal is an RF signal; and

the transmission channel is air.

20. The transmission system of claim 11, wherein:

the transmitter comprises first and second pulse shaping filters, wherein the first pulse shaping filter is selected from the group consisting of a raised-cosine filter and a root-raised-cosine filter, and 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.

21. 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.

22. The method of claim 21, wherein:

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

23. The method of claim 22, wherein:

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

24. The method of claim 23, 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.

25. The method of claim 21, wherein:

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

26. The method of claim 21, wherein:

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

27. The method of claim 21, wherein:

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

28. The method of claim 21, wherein:

the reception signal is an optical signal; and

the transmission channel is an optical channel.

29. The method of claim 21, wherein:

the transmission signal is an RF signal; and

the transmission channel is air.

30. The method of claim 21, wherein:

the shaped pulses are shaped using first and second pulse shaping filters, wherein the first pulse shaping filter is selected from the group consisting of a raised-cosine filter and a root-raised-cosine filter, and 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.