Back to results
US 2010/0135431 A1Published application
Modulating device and method, demodulating device and method
AssigneeElectronics and Telecommunications Research Institute
InventorsDong Kyoo KIM, Jaehwan KIM, Hyung Soo LEE, Jae Young KIM
Life of this patent
Estimating the term…
Abstract
A modulation device uses two base signal axes including a cosine function and two base signal axes including a sine function to modulate bit information and generate a modulation symbol. Accordingly, the frequency efficiency characteristic is improved while maintaining a great power efficiency characteristic.
Claims15
A device for modulating input bit information, comprising:
- a modulation symbol generator for modulating the bit information and generating a modulation symbol by using a plurality of first base signal axes including a cosine function and a plurality of second base signal axes including a sine function;
- and
- a transmitter for transmitting the generated modulation symbol.
A device for demodulating a received signal comprising:
- a first matched filter and a second matched filter respectively having a first filter coefficient and a second filter coefficient respectively matching a first base signal axis and a second base signal axis including a cosine function, filtering the received signal with bandwidths having the first filter coefficient and the second filter coefficient, and outputting filtered signals;
- a third matched filter and a fourth matched filter respectively having a third filter coefficient and a fourth filter coefficient respectively matching the third base signal axis and the fourth base signal axis including a sine function, filtering the received signal with bandwidths having the third filter coefficient and the fourth filter coefficient, and outputting filtered signals;
- a signal determining unit for determining bit information transmitted by a transmitting device by using the filtered signals output by the first to fourth matched filters.
A method for modulating input bit information, comprising:
- generating a plurality of baseband symbols by mapping the bit information on a symbol;
- outputting a first pulse signal that is a product of a first baseband symbol and a cosine function;
- outputting a second pulse signal that is a product of a second baseband symbol and a sine function;
- adding the first pulse signal and the second pulse signal and outputting the added signal;
- and
- generating a modulation symbol by multiplying the added signal and a third baseband symbol.
3 more elements
A method for demodulating a received signal, comprising:
- filtering the received signal with bandwidths having a first filter coefficient and a second filter coefficient respectively matching a first base signal axis and a second base signal axis including a cosine function and a third filter coefficient and a fourth filter coefficient respectively matching a third base signal axis and a fourth base signal axis including a sine function, and outputting a filtered signal;
- and
- determining bit information transmitted by the transmitting device by using the filtered signal.
Dependencies are inferred from the claim text.