Abstract: An apparatus includes a user input unit, a display unit, a control unit, and a buffer unit. The display unit includes a speed setting menu. The control unit selects a mode from the speed setting menu in response to the selection signal of the user, and controls a compression ratio of a voice codec and a transfer rate of a modem corresponding to a transmission-side radio, and a reception rate of a modem and a restoration rate of a voice codec corresponding to a reception-side radio, based on the selected mode. The buffer unit performs a storage function if there is a difference between the compression ratio of the voice codec and the transfer rate of the modem or if there is a difference between the reception rate of the modem and the restoration rate of the voice codec.

Abstract: A secret key generation apparatus and method are provided. The secret key generation apparatus includes at least one antenna, amplification/phase controllers, a transceiver, and a random signal controller. The antenna receives a wireless signal from a counterpart terminal that performs wireless communication. The amplification/phase controllers control the amplification gain and phase of the wireless signal that is received via at least one antenna. The transceiver measures the status of a wireless channel using the wireless signal having the controlled amplification gain and phase, determines parameters based on results of the measurement, and generates a secret key based on results of the determination. The random signal controller controls the amplification/phase controllers so that the amplification gain and phase are adjusted whenever the transceiver generates a secret key.

Abstract: An apparatus includes a user input unit, a display unit, a control unit, and a buffer unit. The display unit includes a speed setting menu. The control unit selects a mode from the speed setting menu in response to the selection signal of the user, and controls a compression ratio of a voice codec and a transfer rate of a modem corresponding to a transmission-side radio, and a reception rate of a modem and a restoration rate of a voice codec corresponding to a reception-side radio, based on the selected mode. The buffer unit performs a storage function if there is a difference between the compression ratio of the voice codec and the transfer rate of the modem or if there is a difference between the reception rate of the modem and the restoration rate of the voice codec.

Abstract: An information protection system includes a mobile terminal and an encryption module. The mobile terminal requests a key sequence by transmitting a message including a Personal Identification Number (PIN) number input by a user, and encrypts or decrypts one or more communication signals, including voice signals and data signals, based on the key sequence when the key sequence is received. The encryption module is connected to the mobile terminal. The encryption module encrypts a security key using the identifier and the PIN number of the mobile terminal, decrypts the encrypted security when requested by the mobile terminal, and transmits the key sequence generated based on the decrypted security key to the mobile terminal.

Abstract: A WCDMA 3G voice communication protection method and a terminal using the method are provided. The method is performed by a terminal operating in conjunction with an S-USIM for voice communication protection. When a calling terminal connects a voice communication channel to a called terminal, secure voice communication is prepared for by collecting information about relevant voice communication. At the calling terminal, synchronous data is set by exchanging the voice communication information with the called terminal, and a secure synchronization procedure is performed based on the set synchronous data. At each of S-USIMs that operate in conjunction with the calling and called terminals, a session key for secure voice communication is generated based on the synchronous data. Secure communication is performed by encrypting and transmitting voice-coded data to be transmitted based on the session key, and decrypting and reproducing received voice-coded data based on the session key.

Abstract: A secret key generation apparatus and method are provided. The secret key generation apparatus includes at least one antenna, amplification/phase controllers, a transceiver, and a random sign& controller. The antenna receives a wireless signal from a counterpart terminal that performs wireless communication. The amplification/phase controllers control the amplification gain and phase of the wireless signal that is received via at least one antenna. The transceiver measures the status of a wireless channel using the wireless signal having the controlled amplification gain and phase, determines parameters based on results of the measurement, and generates a secret key based on results of the determination. The random signal controller controls the amplification/phase controllers so that the amplification gain and phase are adjusted whenever the transceiver generates a secret key.

Abstract: A WCDMA 3G voice communication protection method and a terminal using the method are provided. The method is performed by a terminal operating in conjunction with an S-USIM for voice communication protection. When a calling terminal connects a voice communication channel to a called terminal, secure voice communication is prepared for by collecting information about relevant voice communication. At the calling terminal, synchronous data is set by exchanging the voice communication information with the called terminal, and a secure synchronization procedure is performed based on the set synchronous data. At each of S-USIMs that operate in conjunction with the calling and called terminals, a session key for secure voice communication is generated based on the synchronous data. Secure communication is performed by encrypting and transmitting voice-coded data to be transmitted based on the session key, and decrypting and reproducing received voice-coded data based on the session key.

Abstract: An information protection system includes a mobile terminal and an encryption module. The mobile terminal requests a key sequence by transmitting a message including a Personal Identification Number (PIN) number input by a user, and encrypts or decrypts one or more communication signals, including voice signals and data signals, based on the key sequence when the key sequence is received. The encryption module is connected to the mobile terminal. The encryption module encrypts a security key using the identifier and the PIN number of the mobile terminal, decrypts the encrypted security when requested by the mobile terminal, and transmits the key sequence generated based on the decrypted security key to the mobile terminal.

Abstract: A voice transmission apparatus is provided. The voice transmission apparatus includes a voice input unit, an Analog-to-Digital (AD) converter, a transmission synchronization unit, a channel status determination unit, and a transmission unit. The voice input unit receives an analog voice signal corresponding to a communication session. The AD converter converts the analog voice signal into a digital signal. The transmission synchronization unit generates a transmission target signal by respectively assigning a start identifier and an end identifier to the first frame and final frame of the digital signal corresponding to the communication session. The channel status determination unit determines the status of a channel. The transmission unit transmits the transmission target signal over the channel in such a way that the transmission rate of the transmission target signal is set on a communication session basis depending on the status of the channel.

Abstract: Provided is a method and apparatus for compressing a text and an image. When compressing the text and image, it is possible to group valid lines with data into each line having a common element, and compress and encode the data of the valid lines. Accordingly, it is possible to reduce a data loss that may occur in a tactical communication environment with a poor channel state due to a bit sleep or a burst error. In the case of the text, it is possible to perform lossless compression on only a valid line with data and thereby improve compression efficiency. In the case of the image, it is possible to perform loss compression on valid lines, and then restore the partially damaged data using an ECC even when data is partially damaged. Accordingly, it is possible to improve compression efficiency and the entire data transmission success rate.

Abstract: A parallel processing shrinking key generator is provided. The parallel processing shrinking key generator includes: a selection linear feedback shift register (LFSR); a source LFSR; a selection logic circuit for selecting one of a source bit of the source LFSR and a predetermined input bit according to a selection bit of the selection LFSR; an index counter for assigning an index where output bits of the selection logic circuit are stored at a next clocking of a clock signal; and an output amount register for shifting an output bit of the selection logic circuit according to the assignment of the index counter.

Abstract: Provided is a method and apparatus for compressing a text and an image. When compressing the text and image, it is possible to group valid lines with data into each line having a common element, and compress and encode the data of the valid lines. Accordingly, it is possible to reduce a data loss that may occur in a tactical communication environment with a poor channel state due to a bit sleep or a burst error. In the case of the text, it is possible to perform lossless compression on only a valid line with data and thereby improve compression efficiency. In the case of the image, it is possible to perform loss compression on valid lines, and then restore the partially damaged data using an ECC even when data is partially damaged. Accordingly, it is possible to improve compression efficiency and the entire data transmission success rate.

Abstract: A parallel processing shrinking key generator is provided. The parallel processing shrinking key generator includes: a selection linear feedback shift register (LFSR); a source LFSR; a selection logic circuit for selecting one of a source bit of the source LFSR and a predetermined input bit according to a selection bit of the selection LFSR; an index counter for assigning an index where output bits of the selection logic circuit are stored at a next clocking of a clock signal, and an output amount register for shifting an output bit of the selection logic circuit according to the assignment of the index counter.