In-building radio-frequency coverage

• US 6,501,942 B1
• Filed: 10/29/1999
• Issued: 12/31/2002
• Est. Priority Date: 10/29/1999
• Status: Expired due to Term

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Weissman, Haim, Yona, Eli
• Primary Examiner(s): Nguyen, Lee
• Application Number:
  US09/430,616
• Time in Patent Office: 1,159 Days
• Field of Search: 455/7, 455/14, 455/15, 455/16, 455/20, 455/561, 455/562, 370/315, 375/211, 375/212
• US Class Current: 455/14
• CPC Class Codes: H04B 7/0817 with multiple receivers and antenna path selection
• CPC Class Codes: H04B 7/155 Ground-based stations H04B7/204 takes precedence
• CPC Class Codes: H04W 16/26 Cell enhancers or enhancement, e.g. for tunnels, building shadow
• CPC Class Codes: H04W 88/08 Access point devices

Abstract

Repeater apparatus for conveying a radio-frequency (RF) signal into an environment closed-off to the RF signal, including a master transceiver unit having a master port which receives the RF signal, a local oscillator (LO), which generates a LO signal at a LO frequency, and a frequency divider which divides the LO frequency of the LO signal by an integer to produce a divided LO signal. The master transceiver unit also includes a master mixer coupled to the master port and the divider which generates an intermediate-frequency (IF) signal responsive to the RF signal and the LO signal. The apparatus includes one or more slave transceiver units, each unit positioned within the environment closed-off to the RF signal and including a frequency multiplier which generates a recovered LO signal at the LO frequency by multiplying the frequency of the divided LO signal by the integer, a slave mixer coupled to the multiplier which generates a recovered RF signal responsive to the recovered LO signal and the IF signal, and a slave port coupled to the slave mixer which receives the recovered RF signal therefrom and transmits the recovered RF signal into the closed-off environment. The apparatus further includes one or more cables coupled between the master transceiver unit and the one or more slave transceiver units which convey the IF signal and the divided LO signal between the master transceiver unit and the one or more slave transceiver units.

Claims

1. Repeater apparatus for conveying a radio-frequency (RF) signal into an environment closed-off to the RF signal, comprising:

a. a master transceiver unit, comprising;

i. a master port which receives the RF signal;

ii. a local oscillator (LO), which generates a LO signal at a LO frequency;

iii. a frequency divider which divides the lo frequency of the lo signal by an integer to produce a divided LO signal; and

iv. a master mixer coupled to the master port and the divider which generates an intermediate-frequency (IF) signal responsive to the RF signal and the LO signal;

b. one or more slave transceiver units, each unit positioned within the environment closed-off to the RF signal and comprising;

i. a frequency recovery circuit which generates a recovered LO signal at the LO frequency multiplying the frequency of the divided LO signal by the integer;

ii. a slave mixer coupled to the multiplier which generates a recovered RF signal responsive to the recovered LO signal and the IF signal; and

iii. a slave port coupled to the slave mixer which receives the recovered RF signal therefrom and transmits the recovered RF signal into the closed-off environment; and

iv. an IF signal reverse path comprising a delay element;

c. one or more cables coupled between the master transceiver unit and the one or more slave transceiver units which convey the IF signal and the divided LO signal between the master transceiver unit and the one or more slave transceiver units.

2. Apparatus according to claim 1, wherein the master port is a two-way port, and wherein each slave port is a two-way port through which the respective slave transceiver unit receives an RF slave signal from the closed-off environment and mixes the RF slave signal with the recovered LO signal to produce a slave IF signal which is conveyed by the one or more cables to the master transceiver unit, wherein a recovered slave RF signal is generated and is conveyed to the master port for transmission therefrom.

3. Apparatus according to claim 1, wherein the master transceiver unit comprises an antenna which receives the RF signal from a base transceiver station and transfers the received RF signal to the master port.

4. Apparatus according to claim 1, wherein the master port receives the RF signal via a cable coupled to a base transceiver station.

5. Apparatus according to claim 1, wherein each slave unit comprises one or more antennas coupled to the respective slave port which transmit the recovered RF signal into the closed-off environment.

6. Apparatus according to claim 1, wherein the master unit transceiver comprises a DC power supply which generates a DC level that is conveyed over the one or more cables to power the one or more slave transceiver units.

7. Apparatus according to claim 1, wherein the master unit transceiver comprises a controller which controls the operation of the master transceiver unit and the one or more slave transceiver units.

8. Apparatus according to claim 7, and comprising a remote control unit which transfers control signals between the controller and an operator of the apparatus.

9. Apparatus according to claim 7, wherein the controller generates modulated control signals which are conveyed by the one or more cables between the master transceiver unit and the one or more slave transceiver units.

10. Apparatus according to claim 1, wherein the apparatus operates in a cellular communications network at frequencies substantially in the range 800 MHz to 1900 MHz.

11. Apparatus according to claim 1, wherein the IF signal corresponds to one or more predetermined channels of a multiple-access communications network.

12. Apparatus according to claim 1, wherein the one or more slave transceiver units comprise a plurality of slave transceiver units coupled to the master transceiver unit in one or more daisy-chain topologies.

13. Apparatus according to claim 1, wherein the one or more slave transceiver units comprise a plurality of slave transceiver units coupled to the master transceiver unit in one or more star topologies.

14. Apparatus according to claim 1, wherein the one or more slave transceiver units comprise a plurality of slave transceiver units coupled to the master transceiver unit in one or more hybrid star-daisy-chain topologies.

15. Apparatus according to claim 1, wherein each slave transceiver unit comprises a respective IF signal forward path, wherein the forward path comprises a delay element which delays the IF signal in the forward path by a predetermined time.

16. Apparatus according to claim 1, wherein the frequency recovery circuit comprises a frequency multiplier.

17. A method for conveying a radio-frequency (RF) signal into an environment closed-off to the RF signal, comprising:

a. receiving the RF signal at a master port;

b. providing a local oscillator (LO) signal operating at a LO frequency in a vicinity of the master port;

c. dividing the LO frequency of the LO signal by an integer to produce a divided LO signal;

d. generating an intermediate frequency (IF) signal responsive to the RF signal and the LO signal;

e. conveying the IF signal and the divided LO signal to the closed-off environment;

f. multiplying the frequency of the divided LO signal by the integer to generate a recovered LO signal having the LO frequency;

g. mixing the recovered LO signal and the IF signal to generate a recovered RF signal;

h. coupling the recovered RF signal to a slave port;

i. transmitting the recovered RF signal into the closed-off environment from the slave port;

j. receiving a slave RF signal from the closed-off environment at the slave port;

k. mixing the slave RF signal and the LO signal to produce a slave IF signal;

l. delaying the slave IF signal a predetermined amount;

m. recovering the slave RF signal by mixing the slave IF signal with the LO signal; and

n. transmitting the slave RF signal from the master port.

18. A method according to claim 17, wherein receiving the RF signal comprises receiving a cellular communications transmission at a frequency in the range 800 MHz to 1900 MHz.

19. A method according to claim 17, wherein generating the IF signal comprises producing an IF signal having a frequency substantially less than the frequency of the RF signal.

20. A method according to claim 17, wherein generating the IF signal comprises producing an IF signal having a frequency substantially less than the LO frequency.

21. A method according to claim 17, wherein generating the IF signal comprises producing an IF signal to correspond to one or more predetermined channels of a multiple-access communications network.

22. A method according to claim 17, wherein conveying the IF signal to the closed-off environment comprises delaying the IF signal by a predetermined time.