Time division duplex front end module

• US 7,855,983 B2
• Filed: 06/17/2008
• Issued: 12/21/2010
• Est. Priority Date: 06/14/2006
• Status: Expired due to Fees

• Current Assignee: CTS Corporation
• Original Assignee: CTS Corporation
• Inventors: Knecht, Thomas A., Reeser, Glen
• Primary Examiner(s): Jung; Min
• Application Number:
  US12/214,129
• Publication Number:
  US 20080316948A1
• Time in Patent Office: 917 Days
• Field of Search: None
• US Class Current: 370/280
• CPC Class Codes: H04B 1/18 Input circuits, e.g. for coupling to an antenna or a transmission line coupling networks between antennas or lines and receivers independent of the nature of the receiver H03H
• CPC Class Codes: H04B 1/48 in circuits for connecting transmitter and receiver to a common transmission path, e.g. by energy of transmitter H04B1/46 takes precedence
• CPC Class Codes: H05K 1/0243 Printed circuits associated with mounted high frequency components
• CPC Class Codes: H05K 1/141 One or more single auxiliary printed circuits mounted on a main printed circuit, e.g. modules, adapters H05K1/142 and H05K1/147 take precedence
• CPC Class Codes: H05K 2201/09181 Notches in edge pads
• CPC Class Codes: H05K 2201/1006 Non-printed filter
• CPC Class Codes: H05K 3/3442 having edge contacts, e.g. leadless chip capacitors, chip carriers

Abstract

An RF module adapted for direct surface mounting to the top surface of the front end of the motherboard of a wireless base station such as, for example, a femtocell. The module comprises a printed circuit board having a plurality of direct surface mounted electrical components defining respective signal transmit and receive sections for RF signals. The signal transmit section is defined by at least a power amplifier, a coupler, and a lowpass filter. The signal receive section is defined by at least a receive bandpass filter and a low-noise amplifier. A lid covers selected ones of the electrical components except for at least the power amplifier. An RF switch is located between and interconnects the respective transmit and receive sections to an antenna pin.

Claims

1. A time division duplex RF module adapted for direct-surface mounting to the front end of the motherboard of a base station, the module comprising:

a substrate including top and bottom surfaces, a plurality of peripheral edges including castellations extending between the top and bottom surfaces of the substrate and defining at least voltage input/output pins, and a plurality of vias spaced from the plurality of peripheral edges and extending between the top and bottom surfaces of the substrate and defining at least RF signal input/output pins;

a first section on said substrate coupled to one of the plurality of vias and defining a transmit path for RF signals and including at least a discrete power amplifier;

a second section on said substrate coupled to another of the plurality of vias and defining a receive path for RF signals and including at least the following electrical components;

a discrete receive bandpass filter and a discrete low-noise amplifier; and

a discrete RF switch between and interconnecting said respective first and second sections to an antenna pin defined by yet another of the plurality of vias.

2. The time division duplex RF module of claim 1 further comprising a lid adapted to cover at least said receive bandpass filter and said low-noise amplifier but not said power amplifier.

3. An RF module adapted for direct surface mounting to a front end of a motherboard of a wireless base station and adapted to transmit and receive RF signals, the module comprising:

a substrate including opposed top and bottom surfaces wherein the top surface defines first and second halves, first and second opposed peripheral edges and third and fourth opposed peripheral edges, and first, second, and third RF signal input/output vias extending between the opposed top and bottom surfaces;

an RF signal transmit section on the top surface of the substrate including at least a power amplifier; and

an RF signal receive section on the top surface of said substrate including at least a receive bandpass filter and a low-noise amplifier;

the module being characterized in that the RF signal transmit and receive sections are defined on the first and second halves of the top surface of the substrate respectively, the first and second RF signal input/output vias are defined on the first and second halves of the top surface of the substrate along the first and second opposed peripheral edges of the substrate respectively, and the third RF signal input/output via is defined between the first and second RF signal input/output vias along the third peripheral edge of the substrate.

4. The RF module of claim 3 further comprising a lid adapted to cover at least said RF signal receive section on the top surface of the substrate but not at least said power amplifier of said RF signal transmit section.

5. The RF module of claim 4, wherein at least said receive bandpass filter and said low-noise amplifier are located under said lid.

6. The RF module of claim 3, wherein said substrate defines a plurality of conductive through-holes located below said power amplifier.

7. The RF module of claim 3, wherein an RF switch is located on the top surface of the substrate between and interconnecting said respective RF signal transmit and receive sections and defines a time division duplex RF module.

8. An RF module adapted for direct surface mounting to a front end of a motherboard of a wireless base station, said module including a substrate having a plurality of electrical components mounted thereon and defining respective wireless signal transmit and receive sections thereon, the transmit section including at least a power amplifier mounted to the substrate, the RF module further including a lid which is mounted to the substrate and covers at least a portion of the receive section of the RF module but not at least the power amplifier of the transmit section of the RF module.

9. The RF module of claim 8 wherein the receive section includes at least a receive bandpass filter and the transmit section includes at least a transmit lowpass filter all direct surface mounted to said substrate of said module.

10. The RF module of claim 9 wherein the receive section further includes a low-noise amplifier direct surface mounted to said substrate of said module.

11. The RF module of claim 10 further including an RF switch mounted on the substrate and interconnected to both the transmit and receive sections to define a time division duplex RF module.