Communication system and transmitter

Patent metadata

Field	Value
Publication number	US-10938541-B2
Application number	US-201916272696-A
Country	US
Kind code	B2
Filing date	Feb 11, 2019
Priority date	Aug 12, 2016
Publication date	Mar 2, 2021
Grant date	Mar 2, 2021

Abstract

A communication system includes a plurality of transmitters and a receiving unit. The transmitters are configured to divide signals to be emitted into K part signals and to emit the K part signals using K sub-carriers. K is an integer. The K sub-carriers are frequency bands having a sub-carrier bandwidth and are spaced in frequency. The receiving unit is configured to receive signals emitted by the transmitters. The invention further refers to a transmitter.

First claim

The invention claimed is:

1. Communication system,
comprising a plurality of transmitters ( 20 ) and a receiving unit,
wherein the transmitters are configured to divide signals to be emitted into K part signals and to emit the K part signals using K sub-carriers ( 20 ),
wherein K is an integer,
wherein the K sub-carriers are frequency bands exhibiting a sub-carrier bandwidth,
wherein the K sub-carriers are spaced in frequency, and
wherein the receiving unit is configured to receive signals emitted by the transmitters,
wherein a sub-carrier ( 20 ) of the K sub-carriers ( 20 ) having the lowest frequency is offset to a given frequency by a transmitter-individual offset (O i ), being based on a random variable leading to different locations of the respective K sub-carriers ( 20 ) amongst the transmitters ( 2 ),
or
wherein a sub-carrier ( 20 ) of the K sub-carriers ( 20 ) having the highest frequency is offset to a given frequency by a transmitter-individual offset (O i ), being based on a random variable, leading to different locations of the respective K sub-carriers ( 20 ) amongst the transmitters ( 2 ).

2. Communication system of claim 1 ,
wherein the K sub-carriers are equidistantly spaced in frequency with a sub-carrier distance.

3. Communication system of claim 1 ,
wherein each sub-carrier lies within a sub-slot, and
wherein each sub-slot is a frequency band exhibiting a sub-slot bandwidth.

4. Communication system of claim 3 ,
wherein the sub-slot bandwidth is equal to or greater than the sub-carrier bandwidth.

5. Communication system of claim 3 ,
wherein the sub-slot bandwidth of the sub-slots is equal to or greater than the sum of the sub-carrier bandwidth of the sub-carrier and two times a guard level, and
wherein the guard level is depending on a frequency error associated with the transmitters.

6. Communication system of claim 3 ,
wherein the sub-carrier bandwidth is equal to or smaller than the sub-slot bandwidth of the sub-slots times a frequency utilization based on a probability of transmitters emitting overlapping signals.

7. Communication system of claim 3 ,
wherein a number of sub-slots is chosen with regard to a system capacity describing a rate at which information can be reliably transmitted from the transmitters towards the receiving unit.

8. Communication system of claim 1 ,
wherein a system bandwidth is divided into a plurality of frequency slots exhibiting slot bandwidth, and
wherein each frequency slot is divided into a plurality of sub-slots.

9. Communication system of claim 8 ,
wherein a distance between the sub-slots is based on the slot bandwidth.

10. Communication system of claim 1 ,
wherein a central unit is configured to assign frequency slots and/or sub-slots to transmitters in order to be used for emitting the signals,
and/or
wherein at least one transmitter is configured to select at least one frequency slot and/or at least one sub-slot to be used for emitting the signals.

11. Communication system of claim 7 ,
wherein a number of sub-slots is a positive integer,
wherein the number of sub-slots is smaller than a maximal sub-slot number,
wherein the maximal slot number is depending on a slot bandwidth divided by a guard level, and
wherein the guard level is depending on a frequency error associated with the transmitters.

12. Communication system of claim 1 ,
wherein a number of sub-slots is chosen taking a probability for overlapping signals emitted by different transmitters into account, and
wherein the probability depends on a frequency utilization describing a number of transmitters emitting overlapping signals.

13. Communication system of claim 12 ,
wherein a frequency utilization is depending on a system bandwidth, the number of sub-slots and a guard level depending on a frequency error associated with the transmitters.

14. Communication system of claim 7 ,
wherein the number of frequency slots is set to 1,
or
wherein the number of frequency slots is set such that a slot bandwidth equals a given reference value,
or
wherein the number of frequency slots is set such that the slot bandwidth and a resulting sub-slot bandwidth facilitate calculations.

15. Transmitter,
wherein the transmitter ( 20 ) is configured to divide a signal to be emitted into K part signals and to emit the K part signals using K sub-carriers ( 20 ),
wherein K is an integer, and
wherein the K sub-carriers are frequency bands exhibiting a sub-carrier bandwidth and are spaced in frequency;
wherein a sub-carrier ( 20 ) of the K sub-carriers ( 20 ) having the lowest frequency is offset to a given frequency by a transmitter-individual offset (O i ), being based on a random variable leading to different locations of the respective K sub-carriers ( 20 ) amongst the transmitter ( 2 ) and further transmitters,
or
wherein a sub-carrier ( 20 ) of the K sub-carriers ( 20 ) having the highest frequency is offset to a given frequency by a transmitter-individual offset (O i ), being based on a random variable, leading to different locations of the respective K sub-carriers ( 20 ) amongst the transmitter ( 2 ) and further transmitters.

16. Transmitter of claim 15 ,
wherein one sub-carrier exhibits an offset to a given frequency, and
wherein the offset depends on a frequency error of the transmitter with regard to the emission of signals.

Assignees

• Fraunhofer Ges Forschung

Inventors

• Mayer Frank
• Wansch Rainer

Classifications

• H04B7/18513 Primary

  Transmission in a satellite or space-based system · CPC title

• H04L5/0076

  Allocation utility-based · CPC title

• H04L5/1469

  using time-sharing · CPC title

• H04L5/0064

  Rate requirement of the data, e.g. scalable bandwidth, data priority · CPC title

• H04L5/0007

  the frequencies being orthogonal, e.g. OFDM(A) or DMT · CPC title