Encryption and decryption of chained messages
    1.
    发明授权
    Encryption and decryption of chained messages 失效
    链接消息的加密和解密

    公开(公告)号:US5161189A

    公开(公告)日:1992-11-03

    申请号:US667151

    申请日:1991-03-11

    IPC分类号: H04L9/08 H04L9/12

    摘要: A single sync field (501) and multiple messages or message segments (503, 507, 511, and 515) are chained (407) together and encrypted (407) as a whole. When this encrypted chained message is received, it is decrypted as a whole (605), or in part (613) by setting up (609) and filling (611) a holding register with the encryption state of the encrypting device.

    摘要翻译: 作为整体,单个同步字段(501)和多个消息或消息段(503,507,511和515)被链接(407)在一起并加密(407)。 当接收到加密的链接消息时,通过设置(609)并填充(611)具有加密设备的加密状态的保持寄存器,将其作为整体(605)或部分(613)进行解密。

    Method and apparatus for time companding a digital voice signal
    2.
    发明授权
    Method and apparatus for time companding a digital voice signal 失效
    用于时间压缩数字语音信号的方法和装置

    公开(公告)号:US4893308A

    公开(公告)日:1990-01-09

    申请号:US903315

    申请日:1986-09-03

    IPC分类号: H04B1/66 H04L7/04

    CPC分类号: H04L7/04 H04B1/662

    摘要: Disclosed is a method and apparatus for time companding a digital voice signal wherein, single bits are periodically removed from the digital voice signal, which is then compressed thereby forming a contiguous area of removed bits. A synchronization signal is inserted into this area and the combined signal is transmitted. At the receiver, the synchronization signal is extracted and is used to synchronize the receiver. The digital voice signal is then expanded and the removed bits are predicted and replaced.

    摘要翻译: 公开了一种用于时间压缩数字语音信号的方法和装置,其中从数字语音信号周期性地移除单个比特,然后将其压缩,从而形成连续的去除比特的区域。 将同步信号插入该区域,并传送组合信号。 在接收机处,提取同步信号并用于同步接收机。 然后数字语音信号被扩展,并且去除的位被预测和替换。

    Encryption key management
    4.
    发明授权
    Encryption key management 失效
    加密密钥管理

    公开(公告)号:US5412722A

    公开(公告)日:1995-05-02

    申请号:US114528

    申请日:1993-08-31

    IPC分类号: H04L9/08 H04L9/14 H04B7/204

    摘要: A key management system permits a high degree of autonomous rekeying activity by communication units (105) in a secure communication system (100). Responsive to time reference information transmitted by a key management controller (101), the communication units (105) activate a designated key index at a predetermined activation time. If conditions so indicate, a communication unit may transmit a rekey request.

    摘要翻译: 密钥管理系统通过安全通信系统(100)中的通信单元(105)允许高度自主的密钥密钥活动。 响应于由密钥管理控制器(101)发送的时间参考信息,通信单元(105)在预定的激活时间激活指定的密钥索引。 如果条件如此指示,则通信单元可以发送重新密钥请求。