RECEIVER WITH SIGMA-DELTA STRUCTURE

• US 20090131004A1
• Filed: 06/11/2008
• Published: 05/21/2009
• Est. Priority Date: 11/20/2007
• Status: Active Grant

• Current Assignee: Samsung Electro-Mechanics Co., Ltd. (Samsung Group)
• Original Assignee: Samsung Electro-Mechanics Co., Ltd. (Samsung Group)
• Inventors: Park, Tah Joon, Min, Sang Hyun, KWON, Yong Il
• Granted Patent: US 8,095,100 B2
• Time in Patent Office: Days
• US Class Current: 455/226.200
• CPC Class Codes: H04B 1/0007 wherein the AD/DA conversion occurs at radiofrequency or intermediate frequency stage

Abstract

There is provided a receiver with a sigma-delta structure, the receiver including: a low noise amplifier amplifying a received signal according to a detection signal; a mixer converting an RF signal of the low noise amplifier into an IF signal; a sigma-delta A/D converter converting the IF signal from the mixer 200 into a digital signal; a 1 bit detector determining whether a voltage of the output signal of the mixer is greater than that of a predetermined reference voltage and outputting the detection signal including a result of the determination; and a demodulator obtaining an FFT result with respect to the signal from the sigma-delta A/D converter and adding or subtracting a predetermined gain value to or from the FFT result to calculate received signal strength indication (RSSI).

Claims

1. A receiver with a sigma-delta structure, the receiver comprising:

a low noise amplifier amplifying a received signal according to a detection signal;

a mixer converting an RF signal of the low noise amplifier into an IF signal;

a sigma-delta A/D converter converting the IF signal from the mixer 200 into a digital signal;

a 1 bit detector determining whether a voltage of the output signal of the mixer is greater than that of a predetermined reference voltage and outputting the detection signal including a result of the determination; and

a demodulator obtaining an FFT result with respect to the signal from the sigma-delta A/D converter and adding or subtracting a predetermined gain value to or from the FFT result to calculate received signal strength indication (RSSI).

2. The receiver of claim 1, wherein the 1 bit detector comprises:

a rectifier rectifying the output signal of the mixer and detecting a voltage of the output signal of the mixer; and

a comparator comparing a detection voltage from the rectifier with the reference voltage and outputting the detection signal including a result of the comparison.

3. The receiver of claim 2, wherein the low noise amplifier comprises:

a path switch connecting a received signal input terminal to one of an amplification path and a bypass path according to the detection signal; and

an amplifier provided along the amplification path selected by the path switch and amplifying a signal passing through the path switch 110 and the amplification path.

4. The receiver of claim 2, wherein the demodulator comprises:

an FFT unit obtaining the FFT result with respect to the signal from the sigma-delta A/D converter;

a level determining unit determining a level of the detection signal; and

a received signal strength calculation unit calculating received signal strength indication (RSSI) by subtracting a predetermined gain value from the FFT result according to the level determined by the level determining unit.

5. The receiver of claim 4, the received signal strength indication calculation unit obtains the RSSI by adding a predetermined constant to the FFT result when the level is a weak signal level and obtains the RSSI by adding the predetermined constant to and subtracting the gain value from the FFT result.