Systems and methods for a wireless modem assembly

• US 7,023,909 B1
• Filed: 02/21/2001
• Issued: 04/04/2006
• Est. Priority Date: 02/21/2001
• Status: Active Grant

• Current Assignee: Novatel Wireless, Inc. (Inseego Corp.)
• Original Assignee: Novatel Wireless, Inc. (Inseego Corp.)
• Inventors: Adams, John A., Reeves, Ronald R
• Primary Examiner(s): Corrielus, Jean B.
• Application Number:
  US09/790,428
• Time in Patent Office: 1,868 Days
• Field of Search: 343/700.R, 343/740, 343/702, 343/781.R, 343/781.P, 343/782, 343/821, 343/859, 343/860, 343/865, 343/906, 343/907, 375/222, 375/219, 375/260, 375/259
• US Class Current: 375/222
• CPC Class Codes: H01Q 1/2275 associated to expansion card or bus, e.g. in PCMCIA, PC cards, Wireless USB
• CPC Class Codes: H01Q 1/24 with receiving set
• CPC Class Codes: H01Q 1/38 formed by a conductive layer on an insulating support patch antennas H01Q9/0407; microstrip dipole antennas H01Q9/065; microstrip slot antennas H01Q13/106; transmission line microstrip antennas H01Q13/206; manufacturing reflecting surfaces using insulating material for supporting the reflecting surface H01Q15/142
• CPC Class Codes: H01Q 19/24 the primary active element being centre-fed and substantially straight, e.g. H-antenna
• CPC Class Codes: H01Q 19/30 the primary active element being centre-fed and substantially straight, e.g. Yagi antenna
• CPC Class Codes: H01Q 9/285 Planar dipole H01Q9/065 takes precedence; patch antenna H01Q9/0407

Abstract

A RF wireless modem with an integral antenna. The antenna is a compact, horizontally-polarized, balanced, multi-element, directional antenna with integral balun, constructed on one end of a printed wire board (PWB) and radiating preferably away from the modem circuitry on the remaining portions of PWB. The antenna includes a matching network for matching an impedance of the antenna with an impedance of an unbalanced connection and a balun for transforming a RF transmit signal received from the unbalanced connection into a balanced RF transmit signal. The antenna also includes a radiator for transmitting the balanced RF transmit signal and a reflector for reflecting at least some of the energy of the transmitted signal away from the modem circuitry. The antenna can also include a director for directing the RF transmit signal in a desired direction.

Claims

1. A wireless modem assembly, comprising:

a processor for encoding a baseband transmit signal and receiving a baseband receive signal;

a transceiver for modulating the baseband transmit signal with an RF carrier signal to produce an RF transmit signal and for demodulating an RF receive signal with an RF carrier signal to produce the baseband receive signal;

a horizontally polarized antenna for transmitting the RF transmit signal and for receiving the RF receive signal; and

an unbalanced connection between the transceiver and the antenna, the connection configured to interface the RF transmit signal to the antenna and to interface the RF receive signal to the transceiver, and wherein the antenna comprises;

a matching network for matching an impedance of the unbalanced connection with an impedance of the antenna; and

a balun for transforming the RF transmit signal received from the unbalanced connection into a balanced RF transmit signal.

2. The wireless modem assembly of claim 1, wherein the antenna further comprises a radiator for transmitting the balanced RF transmit signal.

3. The wireless modem assembly of claim 2, wherein the antenna further comprises a reflector for reflecting at least some of the energy of the transmitted signal.

4. The wireless modem assembly of claim 3, wherein the antenna further comprises a plurality of reflectors.

5. The wireless modem of claim 3, wherein the balun is electrically connected to the reflector.

6. The wireless modem assembly of claim 3, wherein the transceiver, and antenna are mounted on a printed wire board that comprises a ground plane, and wherein the ground plane comprises the reflector.

7. The wireless modem assembly of claim 3, wherein the radiator is substantially parallel with a near edge of the reflector, and wherein the spacing between the radiator and the near edge of the reflector is between approximately 0.01 times a design wavelength and approximately 0.1 times the design wavelength.

8. The wireless modem assembly of claim 3, wherein the antenna further comprises a director for directing the transmitted signal in a desired direction.

9. The wireless modem assembly of claim 8, wherein the antenna further comprises a plurality of directors.

10. The wireless modem assembly of claim 8, further comprising a printed wire board wherein at least some of the matching network, balun, radiator, and director are formed of conducting material directly on a top and/or bottom layers of the printed wire board.

11. The wireless modem assembly of claim 10, wherein the printed wire board comprises a plurality of inner layers, wherein each inner layer comprises replicas of the matching network, balun, radiator, or director formed on the top layer of the printed wiring board, and wherein each layer is electrically connected through vias included in the printed wiring board.

12. The wireless modem assembly of claim 8, wherein the director is substantially parallel with the radiator, and wherein the spacing between the radiator and the director is between approximately 0.01 times a design wavelength and approximately 0.1 times the design wavelength.

13. The wireless modem assembly of claim 8, wherein the maximum area of the antenna is approximately 76.2 mm by 35 mm, and wherein the minimum area of the antenna is approximately 10 mm by 4 mm.

14. The wireless modem assembly of claim 8, wherein the area of the antenna is approximately 50 mm by 27 mm.

15. The wireless modem assembly of claim 8, wherein the antenna further comprises a first and second loading inductor, the loading inductors configured to allow the antenna to operate efficiently at a lower frequency than the physical length of the antenna would otherwise allow.

16. The wireless modem assembly of claim 8, wherein the antenna further comprises a first and second trap, the traps configured so that the antenna transmits at two different design frequencies.

17. The wireless modem assembly of claim 16, wherein the first and second traps comprise an inductor and a capacitor in parallel with the inductor.

18. The wireless modem assembly of claim 8, wherein the electrical length of the radiator is approximately half of a design wavelength.

19. The wireless modem assembly of claim 8, wherein the electrical length of the radiator is less than half of a design wavelength.

20. The wireless modem assembly of claim 8, wherein the electrical length of the director is approximately 5 to approximately 30 percent shorter than the electrical length of the radiator.

21. The wireless modem assembly of claim 8, wherein the wireless modem assembly is installed in a computing device, and wherein the reflector reflects some of the energy of the transmitted signal away from the computing device, and wherein the director directs the transmitted signal outward from the computing device.

22. A wireless modem assembly, comprising:

an encoding means for encoding a baseband transmit signal and receiving a baseband receive signal;

a modulation means for modulating the baseband transmit signal with a RF carrier signal to produce a RF transmits signal and for demodulating a RF receive signal with a RF carrier signal to produce the baseband receive signal;

a horizontally polarized transmission means for transmitting the RF transmit signal and for receiving the RF receive signal;

a connection means for connecting the modulation means and the transmission means, and wherein the transmission means comprises;

a matching means for matching an impedance of the connection means with an impedance of the transmission means;

a balancing means for transforming the RF transmit signal into a balanced RF transmit signal;

a radiator means for transmitting the balanced RF transmit signal;

a reflector means for reflecting some of the energy of the transmitted signal; and

a director means for directing the transmitted signal in a desired direction.

23. The wireless modem assembly of claim 22, wherein the maximum area of the transmission means is approximately 76.2 mm by 35 mm, and wherein the minimum area of the transmission means is approximately 10 mm by 4 mm.

24. The wireless modem assembly of claim 22, wherein the area of the transmission means is approximately 50 mm by 27 mm.

25. A horizontally polarized antenna, comprising:

a matching network for matching an impedance of the antenna with an impedance of an unbalanced connection;

a balun for transforming a RF transmit signal received from the unbalanced connection into a balanced RF transmit signal;

a radiator for transmitting the balanced RF transmit signal; and

a reflector for reflecting at least some of the energy of the transmitted signal, the maximum area of the antenna being approximately 76.2 mm by 35 mm, and the minimum area of the antenna being approximately 10 mm by 4 mm.

26. The horizontally polarized antenna of claim 25, wherein the area of the antenna is approximately 50 mm by 27 mm.

27. The horizontally polarized antenna of claim 25 is included in a wireless modem assembly.

28. A horizontally polarized antenna, comprising:

a matching network for matching an impedance of the antenna with an impedance of an unbalanced connection;

a balun for transforming a RF transmit signal received from the unbalanced connection into a balanced RF transmit signal;

a radiator for transmitting the balanced RF transmit signal;

a reflector for reflecting at least some of the energy of the transmitted signal; and

a director for directing the transmitted signal in a desired direction, the maximum area of the antenna being approximately 76.2 mm by 35 mm, and the minimum area of the antenna being approximately 10 mm by 4 mm.

29. The horizontally polarized antenna of claim 28, wherein the area of the antenna is approximately 50 mm by 27 mm.

30. The horizontally polarized antenna of claim 28 is included in a wireless modem assembly.