A downlink interference is dynamically suppressed in a multi-feeder link of a same frequency between an aerial-floating type communication relay apparatus and plural gateway (GW) stations with a simple configuration. A plurality of pilot signals, which are spectrally spread using a plurality of spread codes orthogonal to each other, are transmitted and received between the relay communication station of the aerial-staying type communication relay apparatus and plural GW stations, a propagation path response between plural GW stations and an antenna for feeder link of the communication relay apparatus in a transmission signal band of the feeder link is estimated based on reception results in which the plural pilot signals are spectrally inverse-spread, plural weights respectively corresponding to the plural of GW stations are calculated based on the plural propagation path responses, and with respect to each of the plural GW stations, a signal to be transmitted and received via a directional beam corresponding to another GW station is multiplied by the weight corresponding to the other GW station and subtracted from a signal to be transmitted and received via the directional beam corresponding to the GW station.

A downlink interference is dynamically suppressed in a multi-feeder link of a same frequency between an aerial-floating type communication relay apparatus and plural gateway (GW) stations with a simple configuration. A plurality of pilot signals, which are spectrally spread using a plurality of spread codes orthogonal to each other, are transmitted and received between the relay communication station of the aerial-staying type communication relay apparatus and plural GW stations, a propagation path response between plural GW stations and an antenna for feeder link of the communication relay apparatus in a transmission signal band of the feeder link is estimated based on reception results in which the plural pilot signals are spectrally inverse-spread, plural weights respectively corresponding to the plural of GW stations are calculated based on the plural propagation path responses, and with respect to each of the plural GW stations, a signal to be transmitted and received via a directional beam corresponding to another GW station is multiplied by the weight corresponding to the other GW station and subtracted from a signal to be transmitted and received via the directional beam corresponding to the GW station.

A method and an apparatus are provided for improving a carrier to noise density ratio (CNO) of a matched filter. A signal is received at a signal register of the matched filter. A local code is received at a local code register and a nulling register of the matched filter. An adder tree of the matched filter correlates the signal register and the local code register with respect to the nulling register to obtain a correlation result. The nulling register prevents high frequency samples of the signal register from affecting the correlation result.

A system that incorporates aspects of the subject disclosure may perform operations including, for example, obtaining uplink information associated with a downlink path, wherein the uplink information includes operational parameters used by a plurality of communication devices for transmitting wireless signals on a plurality of uplink paths; performing, based on the uplink information, a plurality of measurements of the plurality of uplink paths; identifying a measurement from the plurality of measurements that is below a threshold, thereby indicating an affected uplink path of the plurality of uplink paths; initiating a first filtering of the affected uplink path, wherein the initiating is based on the identifying and wherein the first filtering is based upon one or more first filtering parameters; and receiving instructions comprising one or more updated filtering parameters, wherein the instructions are received by the system at a port of the system. Other embodiments are disclosed.

A system that incorporates aspects of the subject disclosure may perform operations including, for example, obtaining uplink information associated with a downlink path, wherein the uplink information includes operational parameters used by a plurality of communication devices for transmitting wireless signals on a plurality of uplink paths; performing, based on the uplink information, a plurality of measurements of the plurality of uplink paths; identifying a measurement from the plurality of measurements that is below a threshold, thereby indicating an affected uplink path of the plurality of uplink paths; initiating a first filtering of the affected uplink path, wherein the initiating is based on the identifying and wherein the first filtering is based upon one or more first filtering parameters; and receiving instructions comprising one or more updated filtering parameters, wherein the instructions are received by the system at a port of the system. Other embodiments are disclosed.

The present disclosure describes the concept of operations and the medium access control protocols of a wireless communication system using code-division multiple access with interference avoidance (CDMA-IA) as its physical layer. The system can dynamically share a common band with other networks without a central radio resource controller. In one embodiment, the wireless communication system includes a plurality of radio nodes forming a wireless mesh network, wherein the pairs of radio nodes use, individually optimized, time division duplexing. At least one radio node includes a software-defined radio, a memory, and an electronic processor. The electronic processor is configured to control the software-defined radio to transmit a pilot signal and share various state information with the other nodes of the network. The shared information includes local spectrum occupancy and node connectivity sets. The pervasive sharing of spectrum occupancy among all nodes enables the usage of the shared band to be maximized.

Circuits and methods concerning signal detection are disclosed. In some example embodiments, an apparatus is configured to detect presence of a spreading sequence in a sample data sequence. Phase differences between samples in a sample sequence are determined. Presence of a spreading sequence in the sample sequence is detected by evaluating correlation of reference sub-sequences, of a reference spreading sequence, to the phase differences between samples in a sample sequence. Each of the reference sub-sequences includes fewer chips than the spreading sequence to be detected.

Circuits and methods concerning signal detection are disclosed. In some example embodiments, an apparatus is configured to detect presence of a spreading sequence in a sample data sequence. Phase differences between samples in a sample sequence are determined. Presence of a spreading sequence in the sample sequence is detected by evaluating correlation of reference sub-sequences, of a reference spreading sequence, to the phase differences between samples in a sample sequence. Each of the reference sub-sequences includes fewer chips than the spreading sequence to be detected.

A method of detecting a jamming transmitter includes the steps of indicating that a communication user equipment is capable of communicating in a cellular code division multiple access based radio network; testing a match of a uniform synchronization signal sequence of a synchronization channel; detecting a power indicator indicative of an unbiased wide band power of a received radio signal strength and comparing the power indicator to a noise floor threshold; and indicating a jamming affection of the communication user equipment in the case where (i) the communication indication is on hold; and (ii) the uniform synchronization sequence of the synchronization channel is not matched in the test, and (iii) the power indicator exceeds the noise floor threshold.

A method of detecting a jamming transmitter includes the steps of indicating that a communication user equipment is capable of communicating in a cellular code division multiple access based radio network; testing a match of a uniform synchronization signal sequence of a synchronization channel; detecting a power indicator indicative of an unbiased wide band power of a received radio signal strength and comparing the power indicator to a noise floor threshold; and indicating a jamming affection of the communication user equipment in the case where (i) the communication indication is on hold; and (ii) the uniform synchronization sequence of the synchronization channel is not matched in the test, and (iii) the power indicator exceeds the noise floor threshold.