Signal booster device, a means of transportation comprising a signal booster device and a method for operating a signal booster device

• US 10,236,921 B1
• Filed: 05/31/2018
• Issued: 03/19/2019
• Est. Priority Date: 05/31/2018
• Status: Active Grant

• Current Assignee: Kathrein Automotive GmbH (Continental AG)
• Original Assignee: Kathrein Automotive GmbH (Continental AG)
• Inventors: Kohlhepp, Steffen
• Primary Examiner(s): Rego, Dominic E
• Application Number:
  US15/994,081
• Time in Patent Office: 292 Days
• CPC Class Codes: H01Q 1/246 specially adapted for base stations
• CPC Class Codes: H01Q 1/3291 mounted in or on other locations inside the vehicle or vehicle body
• CPC Class Codes: H04B 1/0458 Arrangements for matching and coupling between power amplifier and antenna or between amplifying stages matching circuits in general H03H
• CPC Class Codes: H04B 7/15 Active relay systems
• CPC Class Codes: H04B 7/15535 Control of relay amplifier gain amplifier gain control in general H03G3/00; gain control reducing self - or loop interference H04B7/15578
• CPC Class Codes: H04B 7/2606 Arrangements for base station coverage control, e.g. by using relays in tunnels
• CPC Class Codes: H04W 72/21 in the uplink direction of a wireless link, i.e. towards the network
• CPC Class Codes: H04W 72/23 in the downlink direction of a wireless link, i.e. towards a terminal

Abstract

A signal booster device comprises a first antenna for communicating with a mobile and a second antenna for communicating with a base station. A signal path connects the antennas to each other. The signal booster device comprises a downlink amplifier, an uplink amplifier and a first downlink power detector for detecting a downlink signal power. The signal booster device comprises a bypass line for directly electrically connecting the first antenna to the second antenna and a control unit configured to obtain a measurement value from the first downlink power detector. The control unit is configured to enable the bypass line if the measurement value of the downlink signal power oversteps a first limit value so that the signal booster device switches from normal operation mode into bypass mode. The downlink amplifier and the uplink amplifier are electrically disconnected from the respective first antenna and second antenna if the bypass line is enabled.

Claims

1. A signal booster device for amplifying signals in a wireless communication network, comprising:

at least one first antenna for communicating with a mobile and at least one second antenna for communicating with a base station,

the signal booster device providing a signal path for electrically connecting the at least one first antenna to the at least one second antenna for transmitting uplink and downlink signals,

the signal path being split up at least partly into a first downlink signal path and into a first uplink signal path,

at least one downlink amplifier for amplifying a downlink signal and at least one uplink amplifier for amplifying an uplink signal,

the at least one downlink amplifier being arranged in the first downlink signal path, the at least one uplink amplifier being arranged in the first uplink signal path,

at least one first downlink power detector for detecting a downlink signal power,

a bypass line for directly electrically connecting the at least one first antenna to the at least one second antenna,

a control unit configured to obtain a measurement value from the at least one first downlink power detector,

the control unit being configured to enable the bypass line if the measurement value of the downlink signal power of the at least one first downlink power detector oversteps a first limit value so that the signal booster device switches from normal operation mode into bypass mode,

the at least one downlink amplifier and the at least one uplink amplifier being electrically disconnected from the respective at least one first antenna and at least one second antenna if the bypass line is enabled.

2. The signal booster device of claim 1, wherein

the signal booster device further comprises a first frequency division unit and a second frequency division unit, each of the first frequency division unit and second frequency division unit having a first downlink port, a first uplink port and a common connecting port,

the at least one first antenna being connected to the common connecting port of the first frequency division unit through a first part of the signal path,

the at least one second antenna being connected to the common connecting port of the second frequency division unit through a second part of the signal path,

the first part of the signal path being split up into a first downlink signal path and into a first uplink signal path by the first frequency division unit, wherein the first downlink signal path is connected to the first downlink port of the first frequency division unit and wherein the first uplink signal path is connected to the first uplink port of the first frequency division unit;

the second part of the signal path being split up into a first downlink signal path and into a first uplink signal path by the second frequency division unit, wherein the first downlink signal path is connected to the first downlink port of the second frequency division unit and wherein the first uplink signal path is connected to the first uplink port of the second frequency division unit;

the device further comprises a first downlink electrical line that electrically connects the first downlink port of the first frequency division unit to the first downlink port of the second frequency division unit thereby providing the first downlink signal path, and a first uplink that electrical line electrically connects the first uplink port of the first frequency division unit to the first uplink port of the second frequency division unit thereby providing the first uplink signal path,

the at least one first downlink power detector being arranged in the first downlink path,

the first and second frequency division units being disconnected from the respective at least one first and second antenna if the bypass line is enabled.

3. The signal booster device of claim 2, wherein

the signal booster device further comprises a first switching circuit and a second switching circuit,

each of the first and second switching circuits having a common connecting port and at least a first and a second connecting port,

each of the first and second switching circuits being configured to electrically connect the respective common connecting port to the respective first connecting port in a first switching state and to electrically connect the respective common connecting port to the respective second connecting port in a second switching state,

the common connecting port of the first switching circuit being electrically connected to the at least one first antenna and the common connecting port of the second switching circuit being electrically connected to the at least one second antenna,

the first connecting port of the first switching circuit being electrically connected to the common connecting port of the first frequency division unit and wherein the first connecting port of the second switching circuit being electrically connected to the common connecting port of the second frequency division unit,

the second connecting port of the first switching circuit being electrically connected to the second connecting port of the second switching circuit thereby forming the bypass line,

the control unit being electrically connected to the first and second switching circuit and configured to control the first and second switching circuits in such a way that the first and second switching circuits switch to the respective first switching state or to the respective second switching state.

4. The signal booster device of claim 3, wherein the first limit value is set to such a value that the bypass line is enabled:

before the uplink and downlink noise power exceeds −

70 dBm/MHz and the uplink gain exceeds the lesser of 23 dB or MSCL (mobile station coupling loss), wherein MSCL is the minimum coupling loss between the mobile and an input port of the signal booster device the at least one first antenna is connected to; and

/or

if a gain of a signal between the first connecting ports of the first and second switching circuits is smaller than a gain of a signal between the second connecting ports of the first and second switching circuits.

5. The signal booster device of claim 3, wherein the control unit is configured to control the first and second switching circuits in such a way that the first and second switching circuits switch to their respective first switching state if the measurement value of the at least one first downlink power detector falls below a second limit value so that the signal booster device is operated in a normal operation mode.

6. The signal booster device of claim 5, wherein the second limit value is:

as high as the first limit value;

or

is below the first limit value.

7. The signal booster device of claim 5, wherein

the control unit is configured to control the first and second switching circuits during the bypass mode in such a way that the first and second switching circuits periodically switch between the second switching state and the first switching state, and

the control unit is further configured to obtain the measurement value from the at least one first downlink power detector in the first switching state.

8. The signal booster device of claim 7, wherein the control unit is configured to control the first and second switching circuits during the bypass mode in such a way that the first and second switching circuits remain longer than 10-times or 20-times or 50-times or 100-times or 200-times or 500-times or 1000-times or 2000-times or 5000-times or 7000-times or 10000-times in the second switching state than in the first switching state.

9. The signal booster device of claim 8, wherein the first switching state lasts longer than 50 μ

s, 60 μ

s, 70 μ

s, 80 μ

s, 90 μ

s, 100 μ

s, 120 μ

s, 140 μ

s, 160 μ

s, 180 μ

s or 200 μ

s but less than 500 μ

s, 400 μ

s, 300 μ

s, 200 μ

s or 150 μ

s.

10. The signal booster device of claim 7, wherein the control unit is further configured to control the at least one first attenuator during the bypass mode in such a way that the at least one first attenuator is driven at least during the first switching state to at least 70% or 80% or 90% of its maximum attenuation.

11. The signal booster device of claim 5, wherein

the signal booster device comprises a second downlink power detector for detecting a downlink signal power in the bypass line, and

the control unit is also configured to obtain a measurement value from the second downlink power detector wherein the control unit is configured to control the first and second switching circuits during the bypass mode with respect to the measurement value obtained from the second downlink power detector.

12. The signal booster device of claim 3, wherein

the signal booster device comprises at least one first attenuator,

the at least one first attenuator is arranged between the first connecting ports of the first and second switching circuits, and

the control unit is configured to control the attenuation factor of the at least one first attenuator.

13. The signal booster device of claim 12, wherein

the at least one first attenuator is arranged between the first connecting port of the first switching circuit and the common connecting port of the first frequency division unit, and/or

the at least one first attenuator is arranged between the first connecting port of the second switching circuit and the common connecting port of the second frequency division unit.

14. The signal booster device of claim 12, wherein

each of the at least one downlink and uplink amplifier is configured to operate at a constant gain, and

the control unit is configured to control the attenuation factor of the least one first attenuator to maintain the output of the signal booster device at the at least one second antenna within the limits required by standards of the cellular industry.

15. The signal booster device of claim 14, wherein

the control unit is configured to control the attenuation factor of the least one first attenuator so that an uplink gain does not exceed −

34 dB—

RSSI+MSCL at a donor port the at least one second antenna is connected to, wherein

RSSI is the downlink composite received signal strength in dBm at the donor port and

MSCL is the minimum coupling loss between the mobile and an input port of the signal booster device the at least one first antenna is connected to.

16. The signal booster device of claim 3, wherein the first and the second switching circuits are SPDT (single pole double throw) semiconductor elements.

17. The signal booster device of claim 2, wherein

the at least one first downlink power detector is arranged in the first downlink path between the first frequency division unit and the at least one downlink amplifier, and/or

the at least one first downlink power detector is arranged in the first downlink path between the second frequency division unit and the at least one downlink amplifier, and/or

the signal booster device comprises at least one first uplink power detector for detecting an uplink signal power, wherein the at least one first uplink power detector is arranged in the first uplink path and wherein the control unit is configured to obtain a measurement value from the at least one first uplink power detector.

18. The signal booster device of claim 2, wherein

the signal booster device is configured to transmit different signals corresponding to at least two different mobile communication bands over the first uplink signal path between the first and second frequency division units,

the signal booster device further comprises a first and a second uplink matching network arranged within the first uplink signal path,

the first uplink matching network is connected to the first frequency division unit and is configured to split the first uplink signal path into at least two uplink branches wherein the first uplink matching network is further configured to forward each of the two mobile communication bands in a different branch,

the second uplink matching network is connected to the second frequency division unit and is configured to merge the at least two uplink branches back into the first uplink signal path,

at least one other uplink amplifier is arranged in each of the at least two uplink branches and is configured to amplify the communication signal of the respective communication band transmitted over the respective uplink branch.

19. The signal booster device of claim 18, wherein at least one other uplink power detector is arranged in each of the at least two uplink branches before and/or after the respective at least one other uplink amplifier, wherein the control unit is configured to obtain a measurement value from the at least one other uplink power detector in each of the at least two uplink branches.

20. The signal booster device of claim 2, wherein the first part of the signal path is also split up into a second downlink signal path and into a second uplink signal path by the first frequency division unit, wherein:

the second downlink signal path is connected to the second downlink port of the first frequency division unit and wherein the second uplink signal path is connected to the second uplink port of the first frequency division unit;

the second part of the signal path is split up into a second downlink signal path and into a second uplink signal path by the second frequency division unit, wherein the second downlink signal path is connected to the second downlink port of the second frequency division unit and wherein the second uplink signal path is connected to the second uplink port of the second frequency division unit;

the first uplink and the first downlink paths are used for transmitting in a low band comprising different mobile communication bands, and

the second uplink and the second downlink paths are used for transmitting in a high band comprising different mobile communication bands.

21. The signal booster device of claim 20, wherein the low band comprises different mobile communication bands below 1000 MHz or below 1200 MHz or below 1400 MHz and wherein:

the high band comprises different mobile communication bands above 1000 MHz or above 1200 MHz or above 1400 MHz, and/or

the low band comprises the mobile communication bands 5, 12, 13, 17 and wherein the high band comprises the mobile communication bands 2, 4.

22. The signal booster device of claim 20, wherein the first downlink signal path and the second downlink signal path are partly merged into a single electrical line, and the at least one downlink amplifier is arranged within the single electrical line.

23. The signal booster device of claim 2, wherein:

the signal booster device is configured to receive signals corresponding to at least two different mobile communication bands over the first downlink signal path,

the signal booster device further comprises a first and a second downlink matching network arranged within the first downlink signal path,

the second downlink matching network is connected to the second frequency division unit and is configured to split the first downlink signal path into at least two downlink branches, wherein the second downlink matching network is further configured to forward each of the at least two mobile communication bands in a different branch,

the first downlink matching network is connected to the first frequency division unit or to the at least one downlink amplifier and wherein the first downlink matching network is configured to merge the at least two downlink branches back into the first downlink signal path, and

at least one other downlink amplifier is arranged in each of the at least two downlink branches and is configured to amplify the communication signal of the respective communication band received over the respective downlink branch.

24. The signal booster device of claim 23, wherein

at least one other downlink power detector is arranged in each of the at least two downlink branches before and/or after the respective at least one other downlink amplifier, and

the control unit is configured to obtain a measurement value from the at least one other downlink power detector in each of the at least two downlink branches.

25. The signal booster device of claim 1, wherein the at least one downlink amplifier and/or the at least one uplink amplifier are low noise amplifiers (LNA).

26. The signal booster device of claim 1, wherein the signal is a 2G, 3G, 4G and/or 5G signal.

27. A transportation platform such as a vehicle, a ship, a train or a plane, wherein the transportation platform comprises a signal booster device according to claim 1, the at least one first antenna is arranged within the transportation platform and the at least one second antenna is arranged on the outside of the transportation platform.

28. A method for amplifying signals in a signal booster device of the type comprising:

at least one first antenna for communicating with a mobile and at least one second antenna for communicating with a base station,

a signal path for electrically connecting the at least one first antenna to the at least one second antenna for transmitting uplink and downlink signals,

at least one downlink amplifier for amplifying a downlink signal and at least one uplink amplifier for amplifying an uplink signal,

at least one first downlink power detector for detecting a downlink signal power,

a bypass line for directly electrically connecting the at least one first antenna to the at least one second antenna,

a control unit configured to obtain a measurement value from the at least one first downlink power detector, the control unit being configured to enable the bypass line,

the method comprising the following steps for amplifying signals;

obtaining a measurement value from the at least one first downlink power detector,

determining whether the measurement value of the at least one first downlink power detector oversteps a first limit value, and

switching from normal operation mode into bypass mode if the measurement value of the at least one first downlink power detector oversteps the first limit value, thereby electrically disconnecting the at least one downlink amplifier and the at least one uplink amplifier from the respective at least one first antenna and at least one second antenna.