Abstract: The present invention provides a system and method of timing estimation for use in a digital, receiver within a communication system. This method exploits the complementary information available from the use of two different nonlinearities to estimate the timing offset following asynchronous sampling of the received signal at a rate of two samples per symbol. The present method operates in a feedforward configuration thereby avoiding issues associated with feedback configurations such as hangup. The present method uses a magnitude square nonlinearity as well as a delay, complex conjugate and multiply nonlinearity to calculate the timing offset. The choice of these nonlinearities is influenced by the need for the estimator to operate in the presence of a phase offset on the received signal. Timing estimators which can tolerate the presence of a slowly varying phase offset over the observation interval on the received signal are especially important in all-digital feedforward receiver design.

Abstract: A method and apparatus for managing a subscription to a product in a retail environment, wherein the product for which a subscription is offered is selected based on the customer's historical purchases. The subscription defines a price for the selected product, wherein the subscription price is lower than the retail price of the product. The subscription specifies conditions which the customer has to meet in order to remain entitled to receive the subscription price for purchases of the product. Such conditions typically include a required frequency of purchases for a required period of time. The conditions of the subscription are selected so as to maximize the customer's visits to the business offering the subscription without unnecessarily eroding the profits of the business.

Abstract: Information is received about a post for an item to be sold. The information may include, for example, the class and type of item being sold, the reputation of a seller, a floor price below which the item will not be sold, a condition of the item and peripherals included with the item. Based on the received information, a posting payment amount is determined.

Abstract: A system and method for communication of radio frequency (RF) signals over multimedia signal paths. The invention provides a wireless multimedia carrier (WMC) system capable of receiving a variety of standardized input signals, such as DS0/E0, T1/E1, T2/E2, and/or T3/E3 for transmission using RF channels. The WMC system selectively employs time division multiple access (TDMA) and/or code division multiple access (CDMA) technology. The WMC system transmits the various signal inputs using RF carriers, receives the transmitted signals, and converts the signals to the desired signaling scheme (standard) for forwarding to intended destinations.

Abstract: A system and method providing a structure to the data sent over the air interface of a wireless communication system. The system and method allow compensation for transmitting and receiving frequency variations, synchronization at the receiver and provision of a virtual signaling channel for system alarms and status. In one embodiment, the system uses bit stuffing, a frame preamble and a signaling preamble to transmit data at a high data rate in the ISM band.

Abstract: A system and method of timing estimation for use in a digital receiver within a communication system. A timing estimation block is provided within a digital receiver, where the input signal is processed at four or more samples per symbol and the estimation block operates in a feedforward manner. The algorithm calculates the timing offset by evaluating the spectral component at the symbol clock frequency. The spectral component is generated using a nonlinearity operation. However, the maximum likelihood non-data-aided timing estimation equation reveals an alternative approximation for the logarithm of the hyperbolic cosine function present in the maximum likelihood equation, which offers an excellent compromise between implementation complexity and variance performance. The estimated timing offset is then fed to a timing correction unit, which calculates the data samples corresponding to the sampling clock phase and removes the redundant samples.

Abstract: A system and method of buffering data of a wireless communication system. The system and method maintain synchronization, end-to-end signaling and coding overhead bits needed to encapsulate data frames sent over wireless media. Additionally, the system and method compensate for transmitting and receiving clock variations. In one embodiment, the system uses framing of data with preamble, stuffing and signaling bits transmitted synchronously at a high data rate in the Industrial, Scientific and Medical (ISM) bands.

Abstract: A system and method of buffering data of a wireless communication system. The system and method maintain synchronization, end-to-end signaling and coding overhead bits needed to encapsulate data frames sent over wireless media. Additionally, the system and method compensate for transmitting and receiving clock variations. In one embodiment, the system uses framing of data with preamble, stuffing and signaling bits transmitted synchronously at a high data rate in the Industrial, Scientific and Medical (ISM) bands.