公开(公告)号：US06574203B2

公开(公告)日：2003-06-03

申请号：US09888913

申请日：2001-06-25

申请人： Neil E. Bernstein ,  Xiao C. Bernstein ,  Wen-Yi Kuo ,  Martin H. Meyers ,  Xiao Wang ,  Carl F. Weaver

发明人： Neil E. Bernstein ,  Xiao C. Bernstein ,  Wen-Yi Kuo ,  Martin H. Meyers ,  Xiao Wang ,  Carl F. Weaver

IPC分类号： H04Q700

CPC分类号： H04W36/30 ,  H04W36/14

摘要： Inter-frequency handoffs in a CDMA or other wireless communication system are controlled using a noise-limited coverage trigger metric which is able to distinguish between same-frequency cell boundaries and other-frequency cell boundaries in the system. The trigger metric may be generated as a function of an average signal-to-noise measure for pilot signals received at a mobile station of the system and a linear sum of the signal-to-noise measures. The signal-to-noise measures may be generated in the mobile station and included in messages transmitted from the mobile station to one or more base stations of the system. The trigger metric is used to control a handoff from a current frequency to a new frequency in an ongoing call. The trigger metric may alternatively be based on a measure of mobile receive power alone. Other aspects of the invention reduce unnecessary searching for a new frequency and decrease the likelihood of “ping-ponging” from a current frequency to a new frequency by providing additional checks in the handoff process. For example, receive power and pilot signal-to-noise measures may be generated at a mobile station for both current and new frequencies. The mobile station then continues to operate at the current frequency as long as certain predetermined threshold conditions based on the measures are satisfied.

公开(公告)号：US06252861B1

公开(公告)日：2001-06-26

申请号：US09048626

申请日：1998-03-26

申请人： Neil E. Bernstein ,  Xiao C. Bernstein ,  Wen-Yi Kuo ,  Martin H. Meyers ,  Xiao Wang ,  Carl F. Weaver

发明人： Neil E. Bernstein ,  Xiao C. Bernstein ,  Wen-Yi Kuo ,  Martin H. Meyers ,  Xiao Wang ,  Carl F. Weaver

IPC分类号： H04Q700

CPC分类号： H04W36/30 ,  H04W36/14

摘要： Inter-frequency handoffs in a CDMA or other wireless communication system are controlled using a noise-limited coverage trigger metric which is able to distinguish between same-frequency cell boundaries and other-frequency cell boundaries in the system. The trigger metric may be generated as a function of an average signal-to-noise measure for pilot signals received at a mobile station of the system and a linear sum of the signal-to-noise measures. The signal-to-noise measures may be generated in the mobile station and included in messages transmitted from the mobile station to one or more base stations of the system. The trigger metric is used to control a handoff from a current frequency to a new frequency in an ongoing call. The trigger metric may alternatively be based on a measure of mobile receive power alone. Other aspects of the invention reduce unnecessary searching for a new frequency and decrease the likelihood of “ping-ponging” from a current frequency to a new frequency by providing additional checks in the handoff process. For example, receive power and pilot signal-to-noise measures may be generated at a mobile station for both current and new frequencies. The mobile station then continues to operate at the current frequency as long as certain predetermined threshold conditions based on the measures are satisfied.

摘要翻译： CDMA或其他无线通信系统中的频率间切换是使用能够区分系统中的同频小区边界和其它频率小区边界的噪声限制覆盖触发度量来控制的。 可以根据在系统的移动台处接收的导频信号的平均信噪比测量值和信噪比测量的线性和来产生触发度量。 信号噪声测量可以在移动台中产生，并且包括在从移动站发送到系统的一个或多个基站的消息中。 触发度量用于控制正在进行的呼叫中从当前频率到新频率的切换。 触发度量可以替代地基于单独的移动接收功率的量度。 本发明的其他方面通过在切换过程中提供额外的检查来减少对新频率的不必要的搜索并且减少从当前频率到新频率的“乒乓”的可能性。 例如，可以在移动台处为当前和新频率产生接收功率和导频信号噪声测量。 只要满足基于措施的某些预定阈值条件，移动台就继续以当前频率工作。