摘要:
A method for use in a field unit operable in a wireless communication network. The method includes receiving an indication of a plurality of access identifiers from a base station. The field unit selects an access identifier from the plurality of access identifiers received from the base station. The selected access identifier is associated with a type of field unit request. The field unit transmits the selected access identifier to the base station. The field unit then receives a message from the base station. The message is based on the transmitted selected access identifier. The message contains a timing adjustment that indicates an amount to advance timing. A corresponding field unit apparatus, a base station method, and corresponding base station apparatus is also disclosed.
摘要:
A method for use in a field unit operable in a wireless communication network. The method includes receiving an indication of a plurality of access identifiers from a base station. The field unit selects an access identifier from the plurality of access identifiers received from the base station. The selected access identifier is associated with a type of field unit request. The field unit transmits the selected access identifier to the base station. The field unit then receives a message from the base station. The message is based on the transmitted selected access identifier. The message contains a timing adjustment that indicates an amount to advance timing. A corresponding field unit apparatus, a base station method, and corresponding base station apparatus is also disclosed.
摘要:
A method for use in a field unit operable in a wireless communication network. The method includes receiving an indication of a plurality of access identifiers from a base station. The field unit selects an access identifier from the plurality of access identifiers received from the base station. The selected access identifier is associated with a type of field unit request. The field unit transmits the selected access identifier to the base station. The field unit then receives a message from the base station. The message is based on the transmitted selected access identifier. The message contains a timing adjustment that indicates an amount to advance timing. A corresponding field unit apparatus, a base station method, and corresponding base station apparatus is also disclosed.
摘要:
Multiple field units in a CDMA system are synchronized for communication with a base station using shared forward and reverse link channels. In an illustrative embodiment, each field unit is assigned a time slot in a forward link channel to receive messages from the base station. Likewise, each field unit is assigned a time slot on a common reverse link channel for transmitting messages to the base station. Timing alignment and power level control among each of many field units and the base station is achieved by analyzing messages received at the base station in a corresponding time slot as transmitted by each field unit. Thereafter, a message is transmitted from the base station in a corresponding time slot to a particular field unit for adjusting its timing or power level so that future messages transmitted from the field unit are received in the appropriate time slot at the base station at a desired power level. In this way, minimal resources are deployed to maintain communication and precise synchronization between a base station and each of multiple users, minimizing collisions between field units transmitting in adjacent time slots on the reverse link. This method reduces the frequency a field unit must rely on the use of a slotted aloha random access channel according to IS-95.
摘要:
Multiple field units in a CDMA system are synchronized for communication with a base station using a shared forward and reverse link channel. Each field unit is assigned a time slot in a forward link channel to receive messages from the base station. Likewise, each field unit is assigned a time slot on a common reverse link channel for transmitting messages to the base station. Timing alignment among each of many field units and the base station is achieved by analyzing messages received at the base station in a corresponding time slot from each field unit. Thereafter, a message is transmitted in a corresponding time slot to a particular field unit from the base station for adjusting its timing so that future messages transmitted from the field unit are received in the appropriate time slot at the base station. In this way, minimal resources are deployed to maintain communication and precise synchronization between a base station and each of multiple users, minimizing collisions between field units transmitting in adjacent time slots on the reverse link.
摘要:
Data rate allocation decisions are made for a communications channel. A message is sent on a communication channel such as on a paging channel. The message indicates a forward Effective Radiate Power (ERP) of a pilot signal transmitted. The remote station then determines the received signal strength of this pilot signal, taking into account receiver gains. The path loss may be estimated as the difference between the forward ERP data value received and the detected received pilot power. This transmit power level information is encoded as a digital data word together with the forward path loss information. Upon transmission, the forward path loss estimate as calculated and the output power value can then help determine the amount of excess power available. This is indicative of the amount of dynamic range available in the transmit power amplifier. Coding rates which require a higher dynamic range may be acceptable for use.
摘要:
A technique for encoding digital communication signals. Data symbols are augmented in pilot symbols inserted at predetermined positions. The pilot augmented sequence is then fed to a deterministic error correction block encoder, such as a turbo product coder, to output a coded sequence. The symbols in the error correction encoded sequence are then rearranged to ensure that the output symbols derived from input pilot symbols are located at regular, predetermined positions. As a result, channel encoding schemes can more easily be used which benefits from power of two length block sizes.
摘要:
The present invention provides for making code rate adjustments and modulation type adjustments in a pseudonoise (PN) encoded CDMA system. Coding rate adjustments may be made by changing the number of information bits per symbol, or Forward Error Code (FEC) coding rate. A forward error correction (FEC) block size is maintained at a constant amount. Therefore, as the number of information bits per symbol are increased, an integer multiple of bits per epoch is always maintained. The scheme permits for a greater flexibility and selection of effective data rates providing information bit rates ranging from, for example, approximately 50 kilobits per second to over 5 mega bits per second (Mbps) in one preferred embodiment.
摘要:
In an illustrative embodiment of the present invention, a reference signal including pilot information is transmitted from a base station to one or multiple field units over a pilot channel. A message is also sent to the field units over a paging channel to indicate an effective radiated power level at which the reference signal is transmitted on the pilot channel. Based on a received power level of the reference signal at a field unit and the effective radiated power level of the reference signal, a forward path loss is estimated at the field unit for the forward link between the base station and field unit. Assuming the path loss in the reverse link is approximately the same as the estimated forward link path loss, the field unit can transmit, a reply message in the reverse link so that the base station generally receives a message at a desired power level.
摘要:
A technique for encoding digital communication signals. Data symbols are augmented in pilot symbols inserted at predetermined positions. The pilot augmented sequence is then fed to a deterministic error correction block encoder, such as a turbo product coder, to output a coded sequence. The symbols in the error correction encoded sequence are then rearranged to ensure that the output symbols derived from input pilot symbols are located at regular, predetermined positions. As a result, channel encoding schemes can more easily be used which benefits from power of two length block sizes.