US 7,548,578 B2Granted

Digital frequency hopping transceiver and method thereof

AssigneeRealtek Semiconductor Corp.

InventorsDer Zheng Liu, Kuo Ming Wu, Kuang Yu Yen

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Abstract

The digital frequency-hopping (FH) transceiver and the method thereof can be applied to FH communication system with a short FH time. The transceiver employs a digital signal processing (DSP) in baseband (BB) circuits to implement FH without need to adjusting the RF carrier frequency. Wherein, the digital FH transmitter performs DSP on a digital BB transmission signal to frequency-hop between BB sub-bands corresponding to sub-bands of a channel, converts it into an analog signal, and then modulates the analog signal to the channel sub-bands for transmission. The digital FH receiver then performs carrier demodulation, analog-to-digital conversion and DSP on a received signal to regain the original digital BB transmission signal.

Claims12

Dependent claims

A receiver, used in a frequency-hopping communication system comprising a transmitter which converts a baseband transmitting signal into a frequency-hopping signal and transmits the frequency-hopping signal to the receiver through a channel comprising N sub-bands, for receiving the frequency-hopping signal, the receiver comprising:

a demodulator for demodulating the frequency-hopping signal into an analog baseband signal according to an oscillation frequency;
a converter, coupled to the demodulator, for converting the analog baseband signal into a digital baseband signal;
and
a frequency-dehopping module, coupled to the converter, for generating a baseband receiving signal according to the digital baseband signal, wherein the baseband receiving signal comprises information of the baseband transmitting signal;
wherein the frequency-dehopping module comprises:
a shift signal generator for generating N shift signals corresponding to the N sub-bands;
N multipliers, coupled to the ADC and the shift signal generator, for multiplying the digital baseband signal with the N shift signals respectively;
N frequency down-converters, each frequency down-converter, coupled to the corresponding multiplier, for down-converting an output of the corresponding multiplier to generating a down-converted signal according to a down-converting factor M;
and
a selector, coupled to the N frequency down-converters, for selectively outputting one of the N down-converted signals from the N frequency down-converters to generate the baseband receiving signal.

7 more elements

A receiving method, used in a frequency-hopping communication system comprising a transmitter which converts a baseband transmitting signal into a frequency-hopping signal and transmits the frequency-hopping signal to a receiver through a channel comprising N sub-bands, for receiving the frequency-hopping signal, the receiving method comprising:

demodulating the frequency-hopping signal into an analog baseband signal according to an oscillation frequency by a demodulator in a receiver of the frequency-hopping communication system;
converting the analog baseband signal into a digital baseband signal by a converter in the receiver;
and
generating a baseband receiving signal according to frequency dehopping of the digital baseband signal by a frequency-dehopping module in the receiver, wherein the baseband receiving signal comprises information of the baseband transmitting signal;
wherein the step of generating the baseband receiving signal comprises:
generating N shift signals corresponding to the N sub-bands by a shift signal generator in the frequency-dehopping module;
multiplying the digital baseband signal with the N shift signals to produce N multiplication results by N multipliers in the frequency-dehopping module;
down-converting the N multiplication results according to a down-converting factor M to generate N down-converted signals by N frequency down-converters in the frequency-dehopping module;
and
selectively outputting one of the N down-converted signals to generate the baseband receiving signal by a selector in the frequency-dehopping module.

7 more elements

Dependencies are inferred from the claim text.

Facts

Application: 11/230,477Filed 21 Sep 2005
Priority: TW 93128794 A23 Sep 2004
Published: US 2006/0062279 A123 Mar 2006
Granted: 16 Jun 2009
Term ends: Not estimatedThe source records don’t support an estimate.

Classification6 codes

H04L 27/2626
Multicarrier modulation systems: arrangements specific to the transmitter only
H04B 1/7136
Using frequency hopping: arrangements for generation of hop frequencies, e.g. using a bank of frequency sources, using continuous tuning or using…
H04L 27/2647
Multicarrier modulation systems: arrangements specific to the receiver only
H04B 2001/71367
Arrangements for generation of hop frequencies, e.g. using a bank of frequency sources, using continuous tuning or using a transform: using a…