As opposed to hybrid automatic repeat request with incremental redundancy (HARQ-IR) that all the resources are occupied to resend the redundant information, cross-packet HARQ (XP-HARQ) allows the introduction of new information into retransmissions to substantially exploit the remaining resources. This letter provides a profound investigation into the outage performance of XP-HARQ. In particular, the exact outage expression of XP-HARQ is derived if the maximum number of transmissions is two, and tight outage bounds are obtained for more than two transmissions. Moreover, the asymptotic outage analysis of XP-HARQ in the high signal-to-noise ratio (SNR) regime is carried out not only to simplify the outage expression, but also to show that full time diversity is achievable by XP-HARQ. The simulation results are eventually presented for verifications.

中文翻译：

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跨包HARQ的中断性能

与占用所有资源以重新发送冗余信息的增量冗余混合自动重复请求 (HARQ-IR) 不同，跨包 HARQ (XP-HARQ) 允许将新信息引入重传以充分利用剩余资源. 这封信对 XP-HARQ 的中断性能进行了深入调查。特别是，如果最大传输次数为两次，则导出 XP-HARQ 的确切中断表达式，并且对于超过两次的传输获得严格的中断界限。此外，在高信噪比（SNR）状态下对 XP-HARQ 进行渐近中断分析不仅是为了简化中断表达式，而且还表明 XP-HARQ 可以实现全时分集。最终呈现仿真结果以供验证。