Repeater system using umbrella base station

Patent metadata

Field	Value
Publication number	US-11722207-B2
Application number	US-202016909855-A
Country	US
Kind code	B2
Filing date	Jun 23, 2020
Priority date	Aug 6, 2019
Publication date	Aug 8, 2023
Grant date	Aug 8, 2023

Abstract

A service-area repeater for deployment in a service area to provide capacity supplied by a base station located remotely from the service-area repeater includes downlink circuitry to receive, via a donor antenna coupled to the service-area repeater, transformed RF downlink signals transmitted from the base station or a base-station repeater, the base station transforming original RF downlink signals or the base-station repeater transforming original RF downlink signals received from the base station to produce the transformed RF downlink signals. The downlink circuitry includes a signal transformation circuit to de-transform the received transformed RF downlink signals to generate non-transformed downlink signals and a frequency correction circuit to apply a frequency correction to the downlink signals to produce corrected downlink signals. The downlink circuitry wirelessly transmits the corrected downlink signals via a coverage antenna to user equipment in the service area.

First claim

What is claimed is:

1. A service-area repeater for deployment in a service area in order to provide capacity supplied by a base station located remotely from the service-area repeater in the service area, the service-area repeater comprising:
downlink circuitry configured to receive, via a donor antenna coupled to the service-area repeater, transformed radio frequency downlink signals transmitted from the base station or a base-station repeater, the base station transforming original radio frequency downlink signals or the base-station repeater transforming original radio frequency downlink signals received from the base station in order to produce the transformed radio frequency downlink signals that cannot be detected by user equipment outside the service area;
wherein the downlink circuitry comprises a first signal transformation circuit configured to de-transform the received transformed radio frequency downlink signals in order to generate downlink signals that are not transformed;
wherein the downlink circuitry further comprises a first frequency correction circuit configured to apply a frequency correction to the downlink signals to produce corrected downlink signals; and
wherein the downlink circuitry is further configured to wirelessly transmit the downlink signals via a coverage antenna to any user equipment in the service area.

2. The service-area repeater of claim 1 , wherein the service-area repeater is configured to transmit the corrected downlink signals via the coverage antenna to any user equipment using an air interface complying with a Terrestrial Trunked Radio (TETRA) standard.

3. The service-area repeater of claim 1 , wherein the service-area repeater further comprises uplink circuitry configured to receive, via the coverage antenna, radio frequency uplink signals from user equipment in the service area, wherein the uplink circuitry is further configured to wirelessly transmit uplink signals via the donor antenna to the base station.

4. The service-area repeater of claim 3 , wherein the uplink circuitry comprises a second signal transformation circuit configured to transform the received radio frequency uplink signals to generate transformed uplink signals, wherein the uplink circuitry further comprises a second frequency correction circuit configured to apply the frequency correction to the transformed uplink signals to generate corrected transformed uplink signals, wherein the uplink circuitry is further configured to wirelessly transmit the corrected transformed uplink signals via the donor antenna to the base station.

5. The service-area repeater of claim 4 , wherein the first signal transformation circuit and the second signal transformation circuit are the same circuit.

6. The service-area repeater of claim 4 , wherein the first frequency correction circuit and the second frequency correction circuit are the same circuit.

7. The service-area repeater of claim 3 , wherein the downlink circuitry further comprises a first frequency shifting circuit configured to shift a frequency of the downlink signals to a supported frequency band of the user equipment, wherein the uplink circuitry further comprises a second frequency shifting circuit configured to shift a frequency of the uplink signals to outside a supported frequency band of the user equipment.

8. The service-area repeater of claim 3 , wherein the uplink circuitry further comprises an uplink muting circuit configured to selectively mute a band, channel, and/or time-slot of the received radio frequency uplink signals.

9. The service-area repeater of claim 1 , wherein the received transformed radio frequency downlink signals are inverted radio frequency downlink signals, wherein the first signal transformation circuit is a first signal inversion circuit configured to de-invert a spectrum of the received transformed radio frequency downlink signals in order to generate downlink signals that are not inverted.

10. The service-area repeater of claim 9 , wherein the first signal transformation circuit is configured to de-invert the spectrum of the received inverted radio frequency downlink signals by:
downconverting the inverted radio frequency downlink signals to an inverted complex baseband signal having an in-phase component and a quadrature component;
swapping the in-phase component and the quadrature component of the inverted complex baseband signal to generate a non-inverted complex baseband signal; and
upconverting the non-inverted complex baseband signal to generate the downlink signals that are not inverted.

11. The service-area repeater of claim 9 , wherein the first signal inversion circuit is configured to de-invert the spectrum of the received inverted radio frequency downlink signals by:
downconverting the inverted radio frequency downlink signals to an inverted complex baseband signal having an in-phase component and a quadrature component;
inverting the in-phase component or the quadrature component of the inverted complex baseband signal to generate a non-inverted complex baseband signal; and
upconverting the non-inverted complex baseband signal to generate the downlink signals that are not inverted.

12. The service-area repeater of claim 9 , wherein the first signal inversion circuit is configured to de-invert the spectrum of the received inverted radio frequency downlink signals by:
downconverting the inverted radio frequency downlink signals using a high-side local oscillator injection in order to generate a frequency inverted lower sideband; and
converting the frequency inverted lower sideband to radio frequency in order to generate the downlink signals that are not inverted.

13. The service-area repeater of claim 1 , wherein the first frequency correction circuit is configured to determine the frequency correction by:
correlating the received transformed radio frequency downlink signals against a known pattern that is transmitted in the received signal;
multiplying the known pattern by a complex conjugate of the correlated pattern in the received signal;
measuring a phase change of the resulting product; and
dividing by a duration of the known pattern to calculate a frequency difference between the known pattern and the received signal.

14. The service-area repeater of claim 1 , wherein the transformed radio frequency downlink signals are modulated using differential quadrature phase shift keying, wherein the first frequency correction circuit is configured to determine the frequency correction by determining a rotation rate of a constellation of the received transformed radio frequency downlink signals.

15. The service-area repeater of claim 1 , wherein the first frequency correction circuit is configured to determine the frequency correction by determining a carrier frequency offset using a synchronization burst of a Terrestrial Trunked Radio (TETRA) signal.

16. A base-station repeater for deployment with a base station configured to supply capacity for serving a service area that is located remotely from the base station and the base-station repeater, the base-station repeater comprising:
downlink circuitry configured to receive downlink signals from the base station;
wherein the downlink circuitry comprises a first signal transformation circuit configured to transform the received downlink signals in order to generate transformed downlink signals that do not comply with a mobile standard; and
wherein the downlink circuitry is further configured to wirelessly transmit the transformed downlink signals via one or more base station antennas to a service-area repeater located in the service ar

Assignees

• Commscope Technologies Llc

Inventors

• Dussmann Alfons
• Mazilu Bogdan George
• Hanson Van Erick
• Maca Gregory Allan

Classifications

• H04B7/15507 Primary

  Relay station based processing for cell extension or control of coverage area, (network planning with network coordinated processing with regard to cell extension H04W16/26; network topologies using dedicated repeater stations H04W84/047; terminal devices adapted for relaying to or from an other terminal H04W88/04) · CPC title

• H04B7/2606 Primary

  Arrangements for base station coverage control, e.g. by using relays in tunnels · CPC title

• H04L27/0014

  Carrier regulation (of chaotic carriers H04L27/001; for multicarrier receivers H04L27/2657) · CPC title

• H04W16/26

  Cell enhancers {or enhancement}, e.g. for tunnels, building shadow · CPC title

• H04W72/21

  in the uplink direction of a wireless link, i.e. towards the network · CPC title