Abstract: A method for improving communication distance accuracy of a transaction system via temperature compensation includes: storing a reference temperature value and a reference field intensity value in a card read micro-controller (101), wherein a temperature sensor (104) is used for detecting an external ambient temperature; based on a difference between the detected external ambient temperature and the reference temperature value, determining at the card read micro-controller (101) whether to perform temperature compensation to an RF field intensity or an equivalent value of the RF field intensity of a SIM card antenna (203), wherein the RF field intensity and the equivalent value of the RF field intensity are received by a card read antenna (103) and are transmitted to the card read micro-controller through a card read RF module (102); transmitting a distance determination result via the card read RF module (102) to the card read antenna (103), which sends the result to an RF SIM card (200).

Abstract: A radio frequency (RF) device includes an RF transceiver, an RF antenna, and a magnetic signal detector. The RF is selected to be in the very high frequency (VHF), ultrahigh frequency (UHF), or super high frequency (SHF) bands such that the shielding effect is reduced and the RF device can be configured as a SIM card disposed inside a cellular phone with an increased RF communication range. The magnetic signal detector is used to sense a magnetic field signal from an RF reader, which includes an RF transceiver, an RF antenna, and a magnetic signal transmitter. The longer communication range afforded by the VHF, UHF, or SHF bands is reduced by the sensing of the magnetic field, thereby providing a communication range control, while the RF device and the RF reader exchange information through the RF channel with improved security as a result of the range control.

Abstract: A method for accessing to radio frequency communication with low-frequency electromagnetic communication is provided. A request side sends an activation request including first random data via a low frequency channel. A requested side receives the activation request, generates and sends an activation response message, including second random data and an identifier of the requested side, according to the first radio frequency communication address. The request side receives and verifies the activation response message, and if the verification is passed, generates and sends a connection request, including third random data, according to the second radio frequency communication address. The requested side receives and verifies the connection request and if the verification is passed, generates and sends a connection response message according to the second radio frequency communication address.

Abstract: A radio frequency (RF) power amplifier includes: a pre-stage amplifier configured to amplify an input power to the RF power amplifier; and a post-stage amplifier configured to amplify an output power of the pre-stage amplifier; wherein the pre-stage amplifier comprises a CMOS (Complementary Metal Oxide Semiconductor) amplifier, and the post-stage amplifier comprises a GaAs (Gallium Arsenide) amplifier or a SiGe (Silicon Germanium) amplifier.

Abstract: Systems, devices, and methods allow quick establishment of short-range, high-speed wireless communications between a host communication device and a slave communication device, where range control is realized through a low-speed connection using signals (such as magnetic signals or ultrasonic signals) different from the high-speed communications. The host communication device includes: a reference unit, a first wireless communication unit, and a first control unit. The reference unit is configured to send a first range reference signal to control a communication range of the wireless communication connection. The slave communication device configured to determine whether the distance satisfies a predetermined range according to the received first range reference signal, and if so, the host communication device and slave communication device quickly establish a wireless communication connection and exchange data according to a predetermined protocol.

Abstract: A mobile terminal is provided with a network lock functionality for a network. The mobile terminal includes a subscriber identity module (SIM) slot configured to host a SIM card or an unlocking device, a control chip, an encryption chip, and a network locking module. The control chip is coupled to the SIM slot through a first interface, the encryption chip is coupled to the SIM slot through the first interface to communicate with a module inserted into the SIM slot, and the network locking module is coupled to the encryption chip through a second interface. Further, the network locking module is configured to perform the network lock functionality. The network locking module also has an “open” state supporting a network unlocking operational mode and a “close” state supporting a network locking operational mode.

Abstract: A method for accessing to radio frequency communication with low-frequency electromagnetic communication includes the steps that a request side sends an activation request including first random data via a low frequency channel; a requested side receives the activation request, generates an activation response message including second random data and an identifier of the requested side, and sends the activation response message according to the first radio frequency communication address; and the request side receives and verifies the activation response message. If the verification is passed, then the request side generates a connection request, including third random data, and sends the connection request according to the second radio frequency communication address. The requested side receives and verifies the connection request.

Abstract: An integrated circuit (IC) card is disclosed. The IC card includes a microprocessor and memory module configured to perform a transaction associated with the IC card, and an interface device providing a power input line from an external source. The IC card also includes a power management module coupled between the microprocessor and memory module and the interface device to convert power from the power input line into electric charge, to store the electric charge internally, and to provide power to the microprocessor and memory module when the external source does not provide sufficient power to the IC card.

Abstract: A mobile terminal is provided with a network lock functionality for a network. The mobile terminal includes a subscriber identity module (SIM) slot configured to host a SIM card or an unlocking device, a control chip, an encryption chip, and a network locking module. The control chip is coupled to the SIM slot through a first interface, the encryption chip is coupled to the SIM slot through the first interface to communicate with a module inserted into the SIM slot, and the network locking module is coupled to the encryption chip through a second interface. Further, the network locking module is configured to perform the network lock functionality. The network locking module also has an “open” state supporting a network unlocking operational mode and a “close” state supporting a network locking operational mode.

Abstract: A method is provided for using bad blocks in flash memory. The method includes placing in a replacement area of the flash memory a special bad block that meets a “still usable” condition from the bad blocks of the flash memory. The method also includes receiving a use request for using the special bad block in the replacement area to store user data, writing the user data into the special bad block, and determining whether the user data is successfully written into the special bad block. Further, the method includes placing the special bad block back into the replacement area for a next use request when it is determined that the user data is not successfully written into the special bad block.

Abstract: A radio frequency (RF) IC card device with very high frequency comprises an IC device (102), a radio frequency interface device (103), an RF antenna (104), an IC card interface (106) and an RF interface (107). Particularly, said RF interface device (103) and the RF interface (107) operate in a frequency band of UHF (ultra high frequency) or SHF (super high frequency); said RF antenna (104) is directly integrated on an IC card (100); the RF IC card device with very high frequency exchanges data with other RF devices via the RF interface (107).

Abstract: A method for improving communication distance accuracy of a transaction system via temperature compensation includes: storing a reference temperature value and a reference field intensity value in a card read micro-controller (101), wherein a temperature sensor (104) is used for detecting an external ambient temperature; based on a difference between the detected external ambient temperature and the reference temperature value, determining at the card read micro-controller (101) whether to perform temperature compensation to an RF field intensity or an equivalent value of the RF field intensity of a SIM card antenna (203), wherein the RF field intensity and the equivalent value of the RF field intensity are received by a card read antenna (103) and are transmitted to the card read micro-controller through a card read RF module (102); transmitting a distance determination result via the card read RF module (102) to the card read antenna (103), which sends the result to an RF SIM card (200).

Abstract: A radio frequency (RF) IC card device with very high frequency comprises an IC device (102), a radio frequency interface device (103), an RF antenna (104), an IC card interface (106) and an RF interface (107). Particularly, said RF interface device (103) and the RF interface (107) operate in a frequency band of UHF (ultra high frequency) or SHF (super high frequency); said RF antenna (104) is directly integrated on an IC card (100); the RF IC card device with very high frequency exchanges data with other RF devices via the RF interface (107).