REMOTE RADIO HEAD UNIT SYSTEM WITH WIDEBAND POWER AMPLIFIER AND METHOD

• US 20150382363A1
• Filed: 06/30/2015
• Published: 12/31/2015
• Est. Priority Date: 12/21/2009
• Status: Active Grant

• Current Assignee: Dali Systems Co., Ltd.
• Original Assignee: Dali Systems Co., Ltd.
• Inventors: Wang, Chengxun, Stapleton, Shawn Patrick
• Granted Patent: US 9,814,053 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H03F 1/0277 Selecting one or more amplifiers from a plurality of amplifiers
• CPC Class Codes: H03F 2200/111 the amplifier being a dual or triple band amplifier, e.g. 900 and 1800 MHz, e.g. switched or not switched, simultaneously or not
• CPC Class Codes: H03F 2200/294 the amplifier being a low noise amplifier [LNA]
• CPC Class Codes: H03F 2200/321 Use of a microprocessor in an amplifier circuit or its control circuit
• CPC Class Codes: H03F 2203/7209 the gated amplifier being switched from a first band to a second band
• CPC Class Codes: H03F 3/19 with semiconductor devices only
• CPC Class Codes: H03F 3/245 with semiconductor devices only
• CPC Class Codes: H03F 3/72 Gated amplifiers, i.e. amplifiers which are rendered operative or inoperative by means of a control signal
• CPC Class Codes: H04B 1/0053 with common antenna for more than one band
• CPC Class Codes: H04B 1/0057 using diplexing or multiplexing filters for selecting the desired band
• CPC Class Codes: H04B 1/006 using switches for selecting the desired band H04B1/0057 takes precedence
• CPC Class Codes: H04B 1/0067 with one or more circuit blocks in common for different bands
• CPC Class Codes: H04B 1/10 Means associated with receiver for limiting or suppressing noise or interference
• CPC Class Codes: H04B 1/123 using adaptive balancing or compensation means adaptive filter circuits and algorithms H03H
• CPC Class Codes: H04B 1/40 Circuits
• CPC Class Codes: H04B 1/525 with means for reducing leakage of transmitter signal into the receiver

Abstract

A remote radio head unit (RRU) system for multiple operating frequency bands, multi-channels, driven by a single or more wide band power amplifiers. More specifically, the present invention enables multiple-bands RRU to use fewer power amplifiers in order to reduce size and cost of the multi-band RRU. The present invention is based on the method of using duplexers and/or interference cancellation system technique to increase the isolation between the transmitter signal and receiver signal of the RRU.

Claims

1. An interference mitigation system for improving isolation between transmitters and receivers in wireless communications systems comprising:

a transmitter that transmits a transmit signal during a first time slot while a switch is in a first position;

a feedback coupler that generates a feedback signal based on the transmit signal, wherein a characteristic of the feedback signal is representative of a characteristic of the transmit signal,

an interference cancellation unit that processes the feedback signal to generate a processed signal;

a receiver that receives an intake signal during a second time slot while the switch is in a second position, wherein the intake signal includes a first component from a signal received by the receiver and a second component from interference from the transmit signal, wherein whether the switch is in the first position or the second position is based on a time-division multiplexing technique; and

a combiner that combines the intake signal received with the processed signal to generate a combined signal.